Aim: To establish an objective, easy-to-use and comprehensive method to analyze corpus cavernosum electromyo- graphic signals (CC-potentials). Methods: CC-potentials were recorded during flaccidity in 23 young hea...Aim: To establish an objective, easy-to-use and comprehensive method to analyze corpus cavernosum electromyo- graphic signals (CC-potentials). Methods: CC-potentials were recorded during flaccidity in 23 young healthy volunteers, with surface electrodes placed on the penile shaft bilaterally. Based on the correlation function of Matlab software, an application program for the analysis of CC-potentials was developed. Individual CC-potentials and their autocorrelation function were evaluated, yielding parameters amplitude (A), duration (D), and dominant frequency (DF). The crosscorrelation function of both longitudinal and bilateral pairs of adjacent electrodes was calculated to assess the similar- ity and mutual delay of CC-potentials recorded simultaneously from different parts of the CC. The parameters derived were squared maximum cross-correlation coefficient (Rmax) and delay (τ). Based on the absolute value of τ and the corresponding inter-electrode distance, propagation velocity (PV) was calculated. Results. The values of the parameters were determined automatically. No significant difference related to the locations of the electrodes for parameters A, D, and DF was detected. The cross-correlation showed that both longitudinal and bilateral CC-potential pairs had highly similar waveforms (the absolute values of Rmax were 0.80 ± 0.05 and 0.87 ± 0.06, respectively). PV of longitudinal pairs was estimated as 6.15 ± 3.98 cm/s. Conclusion: The application program for correlation analysis of CC-potentials is a comprehensive and versatile method to analyze corpus cavernosum electromyographic recordings. Its objectiveness makes multi-center application possible.展开更多
This study compared tankyrase 1 expression and autophagy quantity between erectile dysfunction (ED) and non-ED rats' corpus cavernosum smooth muscle cells (CSMCs). This study aslo explored the effect and possible...This study compared tankyrase 1 expression and autophagy quantity between erectile dysfunction (ED) and non-ED rats' corpus cavernosum smooth muscle cells (CSMCs). This study aslo explored the effect and possible mechanism of tankyrase 1 on autophagy and cell proliferation in ageing ED rats' CSMCs. The intracavernous pres- sure and mean systemic arterial pressure were measured to investigate erectile function so that eight 24-month-old ED and eight 8-month-old male Wistar rats were choosed respectively. The rat CSMCs were isolated and cultured by enzyme digestion, in which tankyrase 1 expression and autophagy quantity were compared. Tankyrase 1 over-expression was induced with plasmid transfection by Lipofectamine^TM. The effect of tankyrase 1 overexpression on proliferation, autophagy and mTOR pathway in 24-month-old ED rats' CSMCs was measured by the cell growth curve in MTT assay, cell cycle analysis in flow cytometry (FCM), key protein expression in Western blot, autophagy quantity in transmission electron microscopy, monodansylcadaverine staining and GFP-LC3 fluorescence. The primary CSMCs were confirmed by immunofluorescence, and the purity was 99.1% in FCM. Compared with that of 8-month-old rats, tankyrase 1 expression and autophagy quantity significantly decreased in 24-month-old ED rats' primary CSMCs (P 〈 0.01). Tankyrase 1 overexpression significantly increased the growth rate (P 〈 0.05) and increased the S phase of cell cycle (P 〈 0.01). The autophagosome quantity was remarkably increased (P 〈 0.01), LC3-Ⅰ/Ⅱ and Beclin 1 were upregulated (P 〈 0.01 and P 〈 0.05), and p-p70S6K (Thr389) was downregulated in 24-month-old ED rat CSMCs (P 〈 0.05). In conclusion, Tankyrase 1 and autophagy decrease in the CSMCs from aging rats with ED, and tankyrase 1 may have a positive effect on proliferation by enhancing autophagy and regulating the mTOR signalling pathway.展开更多
Aim: To further investigate the relaxation mechanism of neferine (NED, a bis-benzylisoquinoline alkaloid extracted (isolated) from the green seed embryo of Nelumbo nucifera Gaertn in China, on rabbit corpus cavern...Aim: To further investigate the relaxation mechanism of neferine (NED, a bis-benzylisoquinoline alkaloid extracted (isolated) from the green seed embryo of Nelumbo nucifera Gaertn in China, on rabbit corpus cavernosum tissue in vitro. Methods: The effects of Nef on the concentrations of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) in isolated and incubated rabbit corpus cavernosum tissue were recorded using ^125I radioimmunoassay. Results: The basal concentration of cAMP in corpus cavernosum tissue was 5.67 ± 0.97 pmol/mg. Nef increased the cAMP concentration in a dose-dependent manner (P 〈 0.05), but this effect was not inhibited by an adenylate cyclase inhibitor (cis-N-[2-phenylcyclopentyl]azacyclotridec-1-en-2-amine, MDL-12, 330A) (P 〉 0.05). The accumulation of cAMP induced by prostaglandin Et (PGEt, a stimulator of cAMP production) was also augmented by Nef in a dose-dependent manner (P 〈 0.05). The basal concentration of cGMP in corpus cavernosum tissue is 0.44 ± 0.09 pmol/mg. Nef did not affect this concentration of cGMP, either in the presence or in the absence of a guanyl cyclase inhibitor (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, ODQ) (P 〉 0.05). Also, sodium nitroprusside (SNP, a stimulator of cGMP production)-induced cGMP production was not enhanced by Nef (P 〉 0.05). Conclusion: Nef, with its relaxation mechanism, can enhance the concentration of cAMP in rabbit corpus cavernosum tissue, probably by inhibiting phosphodiesterase activity. (Asian JAndro12008 Mar; 10: 307-312)展开更多
The effect of Cuscuta chinensis extract on the rabbit penile corpus cavernosum (PCC) was evaluated in the present study. Penises obtained from healthy male New Zealand white rabbits (2.5-3.0 kg) were precontracted...The effect of Cuscuta chinensis extract on the rabbit penile corpus cavernosum (PCC) was evaluated in the present study. Penises obtained from healthy male New Zealand white rabbits (2.5-3.0 kg) were precontracted with phenylephrine (Phe, 10 pmol I^-1) and then treated with various concentrations of Cuscuta chinensis extract (1, 2, 3, 4 and 5 mg ml^-1). The change in penile tension was recorded, and cyclic nucleotides in the PCC were measured by radioimmunoassay (RIA). The interaction between Cuscuta chinensis and sildenafil was also evaluated. The result indicated that the PCC relaxation induced by Cuscuta chinensis extract was concentration-dependent. Pre-treatment with an nitric oxide synthase (NOS) inhibitor (No〉 nitro-L-arginine-methyl ester, L-NAME), a guanylyl cyclase inhibitor (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-l-one, ODQ), or a protein kinase A inhibitor (KT 5720) did not completely inhibit the relaxation. Incubation of penile cavernous tissue with the Cuscuta chinensis extract significantly increased cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) in the PCC. Moreover, the Cuscuta chinensis extract significantly enhanced sildenafil-induced PCC relaxation. In conclusion, the Cuscuta chinensis extract exerts a relaxing effect on penile cavernous tissue in part by activating the NO-cGMP pathway, and it may improve erectile dysfunction (ED), which does not completely respond to sildenafil citrate.展开更多
Aim: To study the effect of sodium nitroprusside (SNP) on the hemodynamics of corpus cavemosum in Chinese menwith erectile dysfunction (ED). Methods; In 68 ED patients receiving intracavemous injection (ICI) of SNP, t...Aim: To study the effect of sodium nitroprusside (SNP) on the hemodynamics of corpus cavemosum in Chinese menwith erectile dysfunction (ED). Methods; In 68 ED patients receiving intracavemous injection (ICI) of SNP, thecavernous hemodynamics were studied by Doppler ultrasonography. Results: The peak flow velocity (PFV), theartery diameter (Ad), the mean velocity of arterial blood (MV) and the vein diameter (Vd) were significantly higherafter ICI of SNP than before ICI, but the end diastolic velocity (EDV) did not change significantly. Conclusion;The increase in Vd after SNP suggests that the venous outflow is not invariably decreased during penile erection.(Asian J Androl 2001 Dec; 3: 311 - 313)展开更多
Summary: To investigate the role of ligustrazine on relaxation of the isolated rabbit corpus cavernosum tissue in vitro, the effects of ligustrazine on the corpus cavernosum were observed by using experimental method...Summary: To investigate the role of ligustrazine on relaxation of the isolated rabbit corpus cavernosum tissue in vitro, the effects of ligustrazine on the corpus cavernosum were observed by using experimental method of smooth muscle strips. Concentration-responses to phenylephine (PE) and KCI were recorded. The results showed that ligustrazine concentration-dependently depressed the contraction response of smooth muscle strips induced by PE. The maximum percentage relaxation of cavernosal strips by ligustrazine was 74.1±6.2 % (compared with control: 21.9±5.6%, P〈0.01). Ligustrazine concentration-dependently reduced the amplitude of the contraction induced by cumulative doses of PE or KCI, shifted the cumulative concentration response curves of PE and KCI to the right and depressed their maximal responses. It was concluded that ligustrazine could significantly relax the cavernosal muscle contraction induced by PE in vitro. The results suggested that ligustrazine inhibited calcium ion influx.展开更多
Objective:To evaluate the effects of testosterone(T)on the maintenance of corpus cavernosum(CC)structure and apoptosis.Methods:Animals were divided into three groups:sham operation group(n Z 8)underwent sham operation...Objective:To evaluate the effects of testosterone(T)on the maintenance of corpus cavernosum(CC)structure and apoptosis.Methods:Animals were divided into three groups:sham operation group(n Z 8)underwent sham operation;Orchiectomized(Orchiec)t oily vehicle group(n Z 8)underwent bilateral orchiectomy and received a single dose of oily vehicle by intramuscular injection(i.m.)30 days after orchiectomy;and Orchiec t T group(n Z 8)underwent bilateral orchiectomy and received a single dose of T undecanoate 100 mg/kg i.m.30 days after the surgery.Animals were euthanized 60 days after the beginning of the experiment with an anesthetic overdose of ketamine and xylazine.Blood samples and penile tissue were collected on euthanasia.展开更多
Aim: To investigate the relaxation mechanisms of neferine (Nef) on the rabbit corpus cavemosum tissue in vitro. Methods: Strips of rabbit corpus cavemosum were mounted in organ chambers. The effects of Nef were ex...Aim: To investigate the relaxation mechanisms of neferine (Nef) on the rabbit corpus cavemosum tissue in vitro. Methods: Strips of rabbit corpus cavemosum were mounted in organ chambers. The effects of Nef were examined on isolated muscle strips precontracted with phenylephrine (PE) alone, in the presence of NW-nitro-L-arginine (LNNA, a nitric oxide synthase inhibitor), 1-H-[ 1,2,4]oxadiazolo[4,3-tx]quinoxalin- 1-one (ODQ, a guanylyl cyclase inhibitor), indomethacin (cyclooxygenase inhibitor), tetraethylammonium (Ca^2+ -activated K^+ channel blocker), 4-aminopiridine (4-AP ,voltage dependent K^+ channel blocker) and glibenclamide (ATP sensitive K^+channel blocker). The effects of Nef on KCl-induced contraction of isolated muscle strips were also investigated. The procedure of calcium absencecalcium addition was designed to observe the effect of Nef on two components of the contractile responses to PE based on the source of Ca^2+ (extracellular vs. intracellular). Results: Corpus cavemosum strips relaxed in response to Nef (10-9-10-4 mol/L) in a concentration-dependent manner with an IC50 of 4.60 × 10^-6 mol/L. However, they were not affected by LNNA, ODQ, indomethacin or K^+-channel blockers. Nef (10^-6 mol/L, 10^-5 mol/L) concentration dependently reduced the maximal contraction response of isolated strips induced by KC1 to 79.3% ± 5.5% and 61.5% ±3.2%, respectively (P 〈 0.01). In the calcium absence-calcium addition procedure, Nef 10.5 mol/L inhibited both intracellular calcium-dependent and extracellular calcium-dependent contraction induced by PE (2 × 10^5 mol/L) (P 〈 0.05). The inhibition ratios were 26.2% ± 5.4% and 48.3% ±7.6%, respectively. Conclusion: The results of the present study suggest that Nef possesses a relaxant effect on rabbit corpus cavemosum tissues, which is attributable to the inhibition of extracellular Ca^2+ influx and the inhibition of release of intracellular stored Ca^2+, but not mediated by the release of nitric oxide, prostaglandins or by the activation of potassium channels.展开更多
Summary: In order to further investigate the mechanisms of action of berberine (Ber), we assessed the effects of Ber on the mRNA expression of nitric oxide synthases (NOS) in rat corpus cavernosum. After incubation wi...Summary: In order to further investigate the mechanisms of action of berberine (Ber), we assessed the effects of Ber on the mRNA expression of nitric oxide synthases (NOS) in rat corpus cavernosum. After incubation with Ber for 1 or 3 h respectively, the levels of NOS mRNA were examined by reverse transcription polymerase chain reaction (RT-PCR). Our results showed that there were iNOS and eNOS mRNA expressions in rat corpus cavernosum. Ber enhanced eNOS mRNA expression in rat penis, but exhibited no effect on the expression of iNOS mRNA (P>0.05). The present study indicated that the relaxation of Ber involved the NO-cGMP signal thansduction pathway. The enhancing effect of Ber on eNOS mRNA expression might associated with its relaxation of corpus cavernosum.展开更多
The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional (3D) scanner to reconstruct cadaveric casts an...The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional (3D) scanner to reconstruct cadaveric casts and compare them with 3D images of two prototypes of penile prosthesis. Two different models of the Titan Coloplast inflatable penile prosthesis were analyzed using a 3D scanner. The first was the standard model and the second was a newer model with a rounder silicone tip. Two cadaveric phalluses were harvested using Smooth-Cast 300Q polyurethane molding. The molds were excised and scanned along side the penile prosthesis. 3D scans were completed and analyzed using Leios Mesh software, and GOM Inspect software. The 3D scans demonstrated the mean human corporal radii 2 mm from the distal tip to be 36.51 mm (36.01-37.0 mm), which is an obtuse angle. The standard Titan penile prosthesis spherical radius at the same level was 202.52 mm, while the new silicone tip prosthesis had a radius of 139.33 mm. 3D mapping further demonstrated the trajectory of the cavernosa appeared curvilinear and the distal ends appeared blunt. The use of cadaveric cavernosal molds in combination with the 3D scanner allowed us to accurately image the corpus cavernosum for the first time. Our findings suggest that anatomically accurate corporal tips appear to be relatively blunt and that the new Titan silicone tip penile prosthesis more closely resembles the human corporal tip.展开更多
Background: Development and maintenance of penile erection requires the relaxation of corpus cavernosum smooth muscle (CCSM) cells and it is essentially mediated by nitric oxide (NO). Pausinystalia yohimbe bark is tra...Background: Development and maintenance of penile erection requires the relaxation of corpus cavernosum smooth muscle (CCSM) cells and it is essentially mediated by nitric oxide (NO). Pausinystalia yohimbe bark is traditionally used for the treatment of erectile dysfunction (ED). Objectives and Methods: This study aimed to evaluate the effects of the methanolic extract of P. yohimbe bark (10 mg/ml) on isolated rabbit corpus cavernosum smooth muscle (CCSM). Results: Methanolic extract of P. yohimbe bark blocked contractions in CCSM induced by adrenergic agonists, through facilitating NO release from the endothelial cells. Conclusion: The obtained results revealed that, methanolic extract of P. yohimbe bark caused relaxation of CCSM that validates its traditional aphrodisiac property, thus it could be used to initiate and maintain erection in cases of erectile dysfunction.展开更多
<strong>Background: </strong>Partial segmental thrombosis of the corpus cavernosum, known as partial priapism, is an uncommon urological condition which predominantly affects young men in which the proxima...<strong>Background: </strong>Partial segmental thrombosis of the corpus cavernosum, known as partial priapism, is an uncommon urological condition which predominantly affects young men in which the proximal part of one corpus cavernosum is thrombosed. Many risk factors have been described in the literature, however, the exact etiology of penile thrombosis and its pathogenesis remains unclear. Several treatment options are available ranging from conservative medical treatment, surgical intervention, or simple follow-up observation without treatment. <strong>Aim:</strong> In this study, we describe a patient with sickle cell anemia who presented with pain and a perineal swelling that was eventually diagnosed as partial priapism utilizing MRI scan and was treated conservatively with a successful outcome. We then performed a literature search of similar cases highlighting incidence, risk factors and management of this rare presentation. <strong>Case Presentation: </strong>A 23-year-old male who is known with sickle cell anemia presented to casualty with a 1-day history of perineal pain of a sudden onset associated with perineal swelling and vomiting. Genitourinary exam findings confirmed the absence of classic priapism. Careful examination of his perineal area revealed the presence of a fixed, hard, and tender mass at the proximal part of the penis. It was not attached to the overlying skin and no enlarged pelvic lymph nodes were felt. Once stabilized, MRI of the pelvis was performed showing right intra-tunical corpus cavernosum features suggestive of hematoma in keeping with partial segmental thrombosis of the corpus cavernosum. Conservative treatment was initiated, and the patient was managed expectantly in which he improved gradually with eventual disappearance of the perineal mass. <strong>Conclusion:</strong> Partial segmental thrombosis of the corpus cavernosum is a rare urological condition. Pathogenesis and etiologies are poorly understood but risk factors have been advocated of which sickle cell anemia is one of them. MRI has a crucial role in the diagnosis under this condition. Conservative treatment appears to be a reliable initial therapeutic option.展开更多
Aim:To study the relaxation mechanisms of tetrandrine(Tet)on the corpus cavernosum smooth muscle.Methods: The corpus cavernosum smooth muscle cells from New Zealand white rabbits were cultured in vitro.[Ca^(2+)]_i was...Aim:To study the relaxation mechanisms of tetrandrine(Tet)on the corpus cavernosum smooth muscle.Methods: The corpus cavernosum smooth muscle cells from New Zealand white rabbits were cultured in vitro.[Ca^(2+)]_i was measured by Fluorescence Ion Digital Imaging System,using Fluo-2/AM as a Ca^(2+)-sensitive fluorescent indicator. Results:Tet(1,10 and 100 μmol/L)had no effect on the resting [Ca^(2+)]_i(P>0.05).In the presence of extracellular Ca^(2+)(2.5 mmol/L),Tet(1,10 and 100 μmol/L)inhibited [Ca^(2+)]_i elevation induced by high K^+ and phenylephrine(PE) in a concentration-dependent manner(P<0.05).In calcium free solution containing egtaic acid,Tet(1 and 10 μmol/L) had no inhibitory effects on [Ca^(2+)]_i elevation induced by PE(P>0.05).However,Tet(100μmol/L)inhibited [Ca^(2+)]_i elevation induced by PE(P<0.05).Conclusion:Tet inhibited the Ca^(2+)influx from the extracellular site via voltage- activated Ca^(2+)channel and α_1-adrenoceptor-operated Ca^(2+)channel.At a high concentration,Tet might inhibit the cytosolic calcium pool release in cultured corpus cavernosum smooth muscle cells.This inhibitory action on [Ca^(2+)]_i might be one of the relaxation mechanisms of Tet on the corpus cavernosum smooth muscle.(Asian J Androl 2006 Jul;8:405-409)展开更多
Background While the abnormal appearance of the concealed penis has been well recognized, the effect of buried penis on the structure and function of corpus cavernosum has not been well studied. To explore this issue,...Background While the abnormal appearance of the concealed penis has been well recognized, the effect of buried penis on the structure and function of corpus cavernosum has not been well studied. To explore this issue, we established a rat model and evaluated the effect of buried penis on cavernosum weight, contents and ultrastructure of tissue, and nitric oxide synthase (NOS) activity. Methods Two hundred and ten rats were randomly divided into 3 equal cohorts for 2, 4 and 6 months study (groups A, B and C). Each group was randomly divided into buried group (n=40), control group (n=15), and normal group (n=15), respectively. Intra-purse-string suture of the root of the penis was used to establish the model. Macroscopic development was judged by measuring the weight of the corpus cavernosum. Masson's trichrome staining was performed for observing microstructure while a transmission electron microscope was used for observing ultrastructure. The NOS activity was detected by a NOS activity assay kit. Results Buried penis had no significant influence on the appearance and weight of the corpus cavernosum. Buried penis resulted in decreased smooth muscle content (P 〉0.05 in group A, and P 〈0.05 in groups B and C) and increased fibrous connective tissue content (P 〉0.05 in groups A and B, and P 〈0.05 in group C) compared with the normal and control groups. Ultrastructural abnormalities of corpus cavernosum were observed in the 6-month buried group. Moreover, there was decrease of NOS activity in groups B and C (P 〈0.05 in group B and P 〈0.01 in group C) when compared with the normal and control groups. Conclusion Buried penis affects the structure and function of corpus cavernosum in rats and the effect is positively correlated with the buried time, but there is no significant effect on the macroscopic development.展开更多
We wanted to determine whether shear wave elastography(SwE)could be used to evaluate the aging degree of the corpus cavernosum(CC)and to identify the histological basis of changes in SWE measurements during the aging ...We wanted to determine whether shear wave elastography(SwE)could be used to evaluate the aging degree of the corpus cavernosum(CC)and to identify the histological basis of changes in SWE measurements during the aging process.We performed a crosssectional study enrolling healthy participants of different ages.We measured the Young's modulus(YM)of the penile CCs by SWE and assessed erectile function using the International Index of Erectile Function-5(IIEF-5).Histological investigation was performed in surgically resected penile specimens from a separate group of patients to examine the smooth muscle and collagen content of the CCs.Furthermore,we measured the YM,erectile function,smooth muscle,and collagen content of the CCs in different age groups of rats.Finally,we enrolled 210 male volunteers in this study.The YM of the CC(CCYM)was positively correlated with age(r=0.949,P<0.01)and negatively correlated with erectile function(r=-0.843,P<0.01).Histological examinations showed that cCs had increased collagen content but decreased smooth muscle content with increased age.The same positive correlation between CcYM and age was also observed in the animal study.In addition,the animal study showed that older rats,with increased CcYM and decreased erectile function,had lower smooth muscle content and higher collagen content.SwE can noninvasively and quantitatively evaluate the aging degree of the Cc.Increased collagen content and decreased smooth muscle content might be the histological basis for the effect of aging on the CC and the increase in its YM.展开更多
Objective: This study investigated the effects of aqueous leaf extract of Tridax procumbens (ALETP) on con- tractile activity of corpus cavernosum in N-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive ...Objective: This study investigated the effects of aqueous leaf extract of Tridax procumbens (ALETP) on con- tractile activity of corpus cavernosum in N-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive male rats. Methods: Twenty normal, adult male rats (130-150 g) were divided into four groups of five rats each. Group I (control) was given normal saline (0.6 mL/kg) and group II was given L-NAME (40 mg/kg) for 6 weeks. Groups Ill and IV also received L-NAME (40 mg/kg) for 6 weeks but were further co-treated with 100 and 200 mg/kg of ALETP, respectively, from week 4 to week 6. All treatments were given orally. Strips of corpus cavernosum from each of the four groups were exposed to increasing concentrations of acetyl~ choline (ACh) and sodium nitroprusside (SNP) (10^-9-10^-5 tool/L) after contraction with phenylephrine (10^-7 mol/L) to test for a dose-response effect, Response to potassium and calcium was also measured after cumulatively adding potassium and calcium (10-50 mmol/L) to potassium- and calcium-free organ chamber. Isometric contractions were recorded through an Ugo Basile data capsule acquisition system. Results: Mean arterial blood pressure was significantly reduced in the ALETP co-treated group compared to the control and L-NAME-only groups (P 〈 0.05). Cavernosa strips from ALETP co-treated rats exhibited significant inhibition of contraction in response to phenylephrine, potassium chloride, and calcium chlo- ride (P 〈 0.05). Relaxation in response to Ach and SNP was also significantly impaired in cavernosa strips from the L-NAME-only treated group (P 〈 0.05), while ALETP co-treated groups showed enhanced per- centage relaxation. Conclusion: ALETP treatment of L-NAME-induced hypertensive rats promotes a relaxant effect on isolated cavernosa strips. ALETP shows potential in correcting erectile dysfunction in hypertension.展开更多
文摘Aim: To establish an objective, easy-to-use and comprehensive method to analyze corpus cavernosum electromyo- graphic signals (CC-potentials). Methods: CC-potentials were recorded during flaccidity in 23 young healthy volunteers, with surface electrodes placed on the penile shaft bilaterally. Based on the correlation function of Matlab software, an application program for the analysis of CC-potentials was developed. Individual CC-potentials and their autocorrelation function were evaluated, yielding parameters amplitude (A), duration (D), and dominant frequency (DF). The crosscorrelation function of both longitudinal and bilateral pairs of adjacent electrodes was calculated to assess the similar- ity and mutual delay of CC-potentials recorded simultaneously from different parts of the CC. The parameters derived were squared maximum cross-correlation coefficient (Rmax) and delay (τ). Based on the absolute value of τ and the corresponding inter-electrode distance, propagation velocity (PV) was calculated. Results. The values of the parameters were determined automatically. No significant difference related to the locations of the electrodes for parameters A, D, and DF was detected. The cross-correlation showed that both longitudinal and bilateral CC-potential pairs had highly similar waveforms (the absolute values of Rmax were 0.80 ± 0.05 and 0.87 ± 0.06, respectively). PV of longitudinal pairs was estimated as 6.15 ± 3.98 cm/s. Conclusion: The application program for correlation analysis of CC-potentials is a comprehensive and versatile method to analyze corpus cavernosum electromyographic recordings. Its objectiveness makes multi-center application possible.
基金Acknowledgment We are grateful to Dr Tamotsu Yoshimori for providing the GFP-LC3 plasmid and Dr H. Seimiya for providing the tankyrase 1 plasmid. This study was supported by the National Natural Science Foundation of China (No. 30772285) and Beijing Municipal Commission of Science Technology, China (No. Z080507030808011).
文摘This study compared tankyrase 1 expression and autophagy quantity between erectile dysfunction (ED) and non-ED rats' corpus cavernosum smooth muscle cells (CSMCs). This study aslo explored the effect and possible mechanism of tankyrase 1 on autophagy and cell proliferation in ageing ED rats' CSMCs. The intracavernous pres- sure and mean systemic arterial pressure were measured to investigate erectile function so that eight 24-month-old ED and eight 8-month-old male Wistar rats were choosed respectively. The rat CSMCs were isolated and cultured by enzyme digestion, in which tankyrase 1 expression and autophagy quantity were compared. Tankyrase 1 over-expression was induced with plasmid transfection by Lipofectamine^TM. The effect of tankyrase 1 overexpression on proliferation, autophagy and mTOR pathway in 24-month-old ED rats' CSMCs was measured by the cell growth curve in MTT assay, cell cycle analysis in flow cytometry (FCM), key protein expression in Western blot, autophagy quantity in transmission electron microscopy, monodansylcadaverine staining and GFP-LC3 fluorescence. The primary CSMCs were confirmed by immunofluorescence, and the purity was 99.1% in FCM. Compared with that of 8-month-old rats, tankyrase 1 expression and autophagy quantity significantly decreased in 24-month-old ED rats' primary CSMCs (P 〈 0.01). Tankyrase 1 overexpression significantly increased the growth rate (P 〈 0.05) and increased the S phase of cell cycle (P 〈 0.01). The autophagosome quantity was remarkably increased (P 〈 0.01), LC3-Ⅰ/Ⅱ and Beclin 1 were upregulated (P 〈 0.01 and P 〈 0.05), and p-p70S6K (Thr389) was downregulated in 24-month-old ED rat CSMCs (P 〈 0.05). In conclusion, Tankyrase 1 and autophagy decrease in the CSMCs from aging rats with ED, and tankyrase 1 may have a positive effect on proliferation by enhancing autophagy and regulating the mTOR signalling pathway.
基金Acknowledgment The authors thank Prof. Jia-Ling Wang for kindly supplying the neferine. The technical support from Prof. Bo-Hua Shu is also greatly appreciated. This study was sponsored by the National Natural Science Foundation of China (No. 30471736) and China Postdoctoral Science Foundation (No. 20070410176).
文摘Aim: To further investigate the relaxation mechanism of neferine (NED, a bis-benzylisoquinoline alkaloid extracted (isolated) from the green seed embryo of Nelumbo nucifera Gaertn in China, on rabbit corpus cavernosum tissue in vitro. Methods: The effects of Nef on the concentrations of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) in isolated and incubated rabbit corpus cavernosum tissue were recorded using ^125I radioimmunoassay. Results: The basal concentration of cAMP in corpus cavernosum tissue was 5.67 ± 0.97 pmol/mg. Nef increased the cAMP concentration in a dose-dependent manner (P 〈 0.05), but this effect was not inhibited by an adenylate cyclase inhibitor (cis-N-[2-phenylcyclopentyl]azacyclotridec-1-en-2-amine, MDL-12, 330A) (P 〉 0.05). The accumulation of cAMP induced by prostaglandin Et (PGEt, a stimulator of cAMP production) was also augmented by Nef in a dose-dependent manner (P 〈 0.05). The basal concentration of cGMP in corpus cavernosum tissue is 0.44 ± 0.09 pmol/mg. Nef did not affect this concentration of cGMP, either in the presence or in the absence of a guanyl cyclase inhibitor (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, ODQ) (P 〉 0.05). Also, sodium nitroprusside (SNP, a stimulator of cGMP production)-induced cGMP production was not enhanced by Nef (P 〉 0.05). Conclusion: Nef, with its relaxation mechanism, can enhance the concentration of cAMP in rabbit corpus cavernosum tissue, probably by inhibiting phosphodiesterase activity. (Asian JAndro12008 Mar; 10: 307-312)
文摘The effect of Cuscuta chinensis extract on the rabbit penile corpus cavernosum (PCC) was evaluated in the present study. Penises obtained from healthy male New Zealand white rabbits (2.5-3.0 kg) were precontracted with phenylephrine (Phe, 10 pmol I^-1) and then treated with various concentrations of Cuscuta chinensis extract (1, 2, 3, 4 and 5 mg ml^-1). The change in penile tension was recorded, and cyclic nucleotides in the PCC were measured by radioimmunoassay (RIA). The interaction between Cuscuta chinensis and sildenafil was also evaluated. The result indicated that the PCC relaxation induced by Cuscuta chinensis extract was concentration-dependent. Pre-treatment with an nitric oxide synthase (NOS) inhibitor (No〉 nitro-L-arginine-methyl ester, L-NAME), a guanylyl cyclase inhibitor (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-l-one, ODQ), or a protein kinase A inhibitor (KT 5720) did not completely inhibit the relaxation. Incubation of penile cavernous tissue with the Cuscuta chinensis extract significantly increased cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) in the PCC. Moreover, the Cuscuta chinensis extract significantly enhanced sildenafil-induced PCC relaxation. In conclusion, the Cuscuta chinensis extract exerts a relaxing effect on penile cavernous tissue in part by activating the NO-cGMP pathway, and it may improve erectile dysfunction (ED), which does not completely respond to sildenafil citrate.
文摘Aim: To study the effect of sodium nitroprusside (SNP) on the hemodynamics of corpus cavemosum in Chinese menwith erectile dysfunction (ED). Methods; In 68 ED patients receiving intracavemous injection (ICI) of SNP, thecavernous hemodynamics were studied by Doppler ultrasonography. Results: The peak flow velocity (PFV), theartery diameter (Ad), the mean velocity of arterial blood (MV) and the vein diameter (Vd) were significantly higherafter ICI of SNP than before ICI, but the end diastolic velocity (EDV) did not change significantly. Conclusion;The increase in Vd after SNP suggests that the venous outflow is not invariably decreased during penile erection.(Asian J Androl 2001 Dec; 3: 311 - 313)
文摘Summary: To investigate the role of ligustrazine on relaxation of the isolated rabbit corpus cavernosum tissue in vitro, the effects of ligustrazine on the corpus cavernosum were observed by using experimental method of smooth muscle strips. Concentration-responses to phenylephine (PE) and KCI were recorded. The results showed that ligustrazine concentration-dependently depressed the contraction response of smooth muscle strips induced by PE. The maximum percentage relaxation of cavernosal strips by ligustrazine was 74.1±6.2 % (compared with control: 21.9±5.6%, P〈0.01). Ligustrazine concentration-dependently reduced the amplitude of the contraction induced by cumulative doses of PE or KCI, shifted the cumulative concentration response curves of PE and KCI to the right and depressed their maximal responses. It was concluded that ligustrazine could significantly relax the cavernosal muscle contraction induced by PE in vitro. The results suggested that ligustrazine inhibited calcium ion influx.
基金We thank Urogenital Research Unit staff,UERJ,for technical support and UFCSPA,CNPq(MCT/CNPq 15/2007),Coordenac¸a˜o de Aperfeic¸oamento de Pessoal de Nıvel Superior e CAPES and FAPERGS(11/1003-5 e 02/2011)for financial support.
文摘Objective:To evaluate the effects of testosterone(T)on the maintenance of corpus cavernosum(CC)structure and apoptosis.Methods:Animals were divided into three groups:sham operation group(n Z 8)underwent sham operation;Orchiectomized(Orchiec)t oily vehicle group(n Z 8)underwent bilateral orchiectomy and received a single dose of oily vehicle by intramuscular injection(i.m.)30 days after orchiectomy;and Orchiec t T group(n Z 8)underwent bilateral orchiectomy and received a single dose of T undecanoate 100 mg/kg i.m.30 days after the surgery.Animals were euthanized 60 days after the beginning of the experiment with an anesthetic overdose of ketamine and xylazine.Blood samples and penile tissue were collected on euthanasia.
基金Acknowledgment The authors thank Prof. Jia-Ling Wang for kindly supplying the Nef. The technical assistance from Mr Jun Pan (Department of Urology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China) is also greatly appreciated. This study was sponsored in part by the National Natural Science Foundation of China (No. 30471736).
文摘Aim: To investigate the relaxation mechanisms of neferine (Nef) on the rabbit corpus cavemosum tissue in vitro. Methods: Strips of rabbit corpus cavemosum were mounted in organ chambers. The effects of Nef were examined on isolated muscle strips precontracted with phenylephrine (PE) alone, in the presence of NW-nitro-L-arginine (LNNA, a nitric oxide synthase inhibitor), 1-H-[ 1,2,4]oxadiazolo[4,3-tx]quinoxalin- 1-one (ODQ, a guanylyl cyclase inhibitor), indomethacin (cyclooxygenase inhibitor), tetraethylammonium (Ca^2+ -activated K^+ channel blocker), 4-aminopiridine (4-AP ,voltage dependent K^+ channel blocker) and glibenclamide (ATP sensitive K^+channel blocker). The effects of Nef on KCl-induced contraction of isolated muscle strips were also investigated. The procedure of calcium absencecalcium addition was designed to observe the effect of Nef on two components of the contractile responses to PE based on the source of Ca^2+ (extracellular vs. intracellular). Results: Corpus cavemosum strips relaxed in response to Nef (10-9-10-4 mol/L) in a concentration-dependent manner with an IC50 of 4.60 × 10^-6 mol/L. However, they were not affected by LNNA, ODQ, indomethacin or K^+-channel blockers. Nef (10^-6 mol/L, 10^-5 mol/L) concentration dependently reduced the maximal contraction response of isolated strips induced by KC1 to 79.3% ± 5.5% and 61.5% ±3.2%, respectively (P 〈 0.01). In the calcium absence-calcium addition procedure, Nef 10.5 mol/L inhibited both intracellular calcium-dependent and extracellular calcium-dependent contraction induced by PE (2 × 10^5 mol/L) (P 〈 0.05). The inhibition ratios were 26.2% ± 5.4% and 48.3% ±7.6%, respectively. Conclusion: The results of the present study suggest that Nef possesses a relaxant effect on rabbit corpus cavemosum tissues, which is attributable to the inhibition of extracellular Ca^2+ influx and the inhibition of release of intracellular stored Ca^2+, but not mediated by the release of nitric oxide, prostaglandins or by the activation of potassium channels.
基金This project was supported by a grant from the National Natural Science Foundation of China (No. 30171151).
文摘Summary: In order to further investigate the mechanisms of action of berberine (Ber), we assessed the effects of Ber on the mRNA expression of nitric oxide synthases (NOS) in rat corpus cavernosum. After incubation with Ber for 1 or 3 h respectively, the levels of NOS mRNA were examined by reverse transcription polymerase chain reaction (RT-PCR). Our results showed that there were iNOS and eNOS mRNA expressions in rat corpus cavernosum. Ber enhanced eNOS mRNA expression in rat penis, but exhibited no effect on the expression of iNOS mRNA (P>0.05). The present study indicated that the relaxation of Ber involved the NO-cGMP signal thansduction pathway. The enhancing effect of Ber on eNOS mRNA expression might associated with its relaxation of corpus cavernosum.
文摘The intricate anatomy of the corpus cavernosum in both the flaccid and tumescent state has not been fully elucidated. We report our experience using a three-dimensional (3D) scanner to reconstruct cadaveric casts and compare them with 3D images of two prototypes of penile prosthesis. Two different models of the Titan Coloplast inflatable penile prosthesis were analyzed using a 3D scanner. The first was the standard model and the second was a newer model with a rounder silicone tip. Two cadaveric phalluses were harvested using Smooth-Cast 300Q polyurethane molding. The molds were excised and scanned along side the penile prosthesis. 3D scans were completed and analyzed using Leios Mesh software, and GOM Inspect software. The 3D scans demonstrated the mean human corporal radii 2 mm from the distal tip to be 36.51 mm (36.01-37.0 mm), which is an obtuse angle. The standard Titan penile prosthesis spherical radius at the same level was 202.52 mm, while the new silicone tip prosthesis had a radius of 139.33 mm. 3D mapping further demonstrated the trajectory of the cavernosa appeared curvilinear and the distal ends appeared blunt. The use of cadaveric cavernosal molds in combination with the 3D scanner allowed us to accurately image the corpus cavernosum for the first time. Our findings suggest that anatomically accurate corporal tips appear to be relatively blunt and that the new Titan silicone tip penile prosthesis more closely resembles the human corporal tip.
文摘Background: Development and maintenance of penile erection requires the relaxation of corpus cavernosum smooth muscle (CCSM) cells and it is essentially mediated by nitric oxide (NO). Pausinystalia yohimbe bark is traditionally used for the treatment of erectile dysfunction (ED). Objectives and Methods: This study aimed to evaluate the effects of the methanolic extract of P. yohimbe bark (10 mg/ml) on isolated rabbit corpus cavernosum smooth muscle (CCSM). Results: Methanolic extract of P. yohimbe bark blocked contractions in CCSM induced by adrenergic agonists, through facilitating NO release from the endothelial cells. Conclusion: The obtained results revealed that, methanolic extract of P. yohimbe bark caused relaxation of CCSM that validates its traditional aphrodisiac property, thus it could be used to initiate and maintain erection in cases of erectile dysfunction.
文摘<strong>Background: </strong>Partial segmental thrombosis of the corpus cavernosum, known as partial priapism, is an uncommon urological condition which predominantly affects young men in which the proximal part of one corpus cavernosum is thrombosed. Many risk factors have been described in the literature, however, the exact etiology of penile thrombosis and its pathogenesis remains unclear. Several treatment options are available ranging from conservative medical treatment, surgical intervention, or simple follow-up observation without treatment. <strong>Aim:</strong> In this study, we describe a patient with sickle cell anemia who presented with pain and a perineal swelling that was eventually diagnosed as partial priapism utilizing MRI scan and was treated conservatively with a successful outcome. We then performed a literature search of similar cases highlighting incidence, risk factors and management of this rare presentation. <strong>Case Presentation: </strong>A 23-year-old male who is known with sickle cell anemia presented to casualty with a 1-day history of perineal pain of a sudden onset associated with perineal swelling and vomiting. Genitourinary exam findings confirmed the absence of classic priapism. Careful examination of his perineal area revealed the presence of a fixed, hard, and tender mass at the proximal part of the penis. It was not attached to the overlying skin and no enlarged pelvic lymph nodes were felt. Once stabilized, MRI of the pelvis was performed showing right intra-tunical corpus cavernosum features suggestive of hematoma in keeping with partial segmental thrombosis of the corpus cavernosum. Conservative treatment was initiated, and the patient was managed expectantly in which he improved gradually with eventual disappearance of the perineal mass. <strong>Conclusion:</strong> Partial segmental thrombosis of the corpus cavernosum is a rare urological condition. Pathogenesis and etiologies are poorly understood but risk factors have been advocated of which sickle cell anemia is one of them. MRI has a crucial role in the diagnosis under this condition. Conservative treatment appears to be a reliable initial therapeutic option.
文摘Aim:To study the relaxation mechanisms of tetrandrine(Tet)on the corpus cavernosum smooth muscle.Methods: The corpus cavernosum smooth muscle cells from New Zealand white rabbits were cultured in vitro.[Ca^(2+)]_i was measured by Fluorescence Ion Digital Imaging System,using Fluo-2/AM as a Ca^(2+)-sensitive fluorescent indicator. Results:Tet(1,10 and 100 μmol/L)had no effect on the resting [Ca^(2+)]_i(P>0.05).In the presence of extracellular Ca^(2+)(2.5 mmol/L),Tet(1,10 and 100 μmol/L)inhibited [Ca^(2+)]_i elevation induced by high K^+ and phenylephrine(PE) in a concentration-dependent manner(P<0.05).In calcium free solution containing egtaic acid,Tet(1 and 10 μmol/L) had no inhibitory effects on [Ca^(2+)]_i elevation induced by PE(P>0.05).However,Tet(100μmol/L)inhibited [Ca^(2+)]_i elevation induced by PE(P<0.05).Conclusion:Tet inhibited the Ca^(2+)influx from the extracellular site via voltage- activated Ca^(2+)channel and α_1-adrenoceptor-operated Ca^(2+)channel.At a high concentration,Tet might inhibit the cytosolic calcium pool release in cultured corpus cavernosum smooth muscle cells.This inhibitory action on [Ca^(2+)]_i might be one of the relaxation mechanisms of Tet on the corpus cavernosum smooth muscle.(Asian J Androl 2006 Jul;8:405-409)
基金This study was supported by a grant from the National Natural Science Foundation of China (No. 30801145).
文摘Background While the abnormal appearance of the concealed penis has been well recognized, the effect of buried penis on the structure and function of corpus cavernosum has not been well studied. To explore this issue, we established a rat model and evaluated the effect of buried penis on cavernosum weight, contents and ultrastructure of tissue, and nitric oxide synthase (NOS) activity. Methods Two hundred and ten rats were randomly divided into 3 equal cohorts for 2, 4 and 6 months study (groups A, B and C). Each group was randomly divided into buried group (n=40), control group (n=15), and normal group (n=15), respectively. Intra-purse-string suture of the root of the penis was used to establish the model. Macroscopic development was judged by measuring the weight of the corpus cavernosum. Masson's trichrome staining was performed for observing microstructure while a transmission electron microscope was used for observing ultrastructure. The NOS activity was detected by a NOS activity assay kit. Results Buried penis had no significant influence on the appearance and weight of the corpus cavernosum. Buried penis resulted in decreased smooth muscle content (P 〉0.05 in group A, and P 〈0.05 in groups B and C) and increased fibrous connective tissue content (P 〉0.05 in groups A and B, and P 〈0.05 in group C) compared with the normal and control groups. Ultrastructural abnormalities of corpus cavernosum were observed in the 6-month buried group. Moreover, there was decrease of NOS activity in groups B and C (P 〈0.05 in group B and P 〈0.01 in group C) when compared with the normal and control groups. Conclusion Buried penis affects the structure and function of corpus cavernosum in rats and the effect is positively correlated with the buried time, but there is no significant effect on the macroscopic development.
文摘We wanted to determine whether shear wave elastography(SwE)could be used to evaluate the aging degree of the corpus cavernosum(CC)and to identify the histological basis of changes in SWE measurements during the aging process.We performed a crosssectional study enrolling healthy participants of different ages.We measured the Young's modulus(YM)of the penile CCs by SWE and assessed erectile function using the International Index of Erectile Function-5(IIEF-5).Histological investigation was performed in surgically resected penile specimens from a separate group of patients to examine the smooth muscle and collagen content of the CCs.Furthermore,we measured the YM,erectile function,smooth muscle,and collagen content of the CCs in different age groups of rats.Finally,we enrolled 210 male volunteers in this study.The YM of the CC(CCYM)was positively correlated with age(r=0.949,P<0.01)and negatively correlated with erectile function(r=-0.843,P<0.01).Histological examinations showed that cCs had increased collagen content but decreased smooth muscle content with increased age.The same positive correlation between CcYM and age was also observed in the animal study.In addition,the animal study showed that older rats,with increased CcYM and decreased erectile function,had lower smooth muscle content and higher collagen content.SwE can noninvasively and quantitatively evaluate the aging degree of the Cc.Increased collagen content and decreased smooth muscle content might be the histological basis for the effect of aging on the CC and the increase in its YM.
文摘Objective: This study investigated the effects of aqueous leaf extract of Tridax procumbens (ALETP) on con- tractile activity of corpus cavernosum in N-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive male rats. Methods: Twenty normal, adult male rats (130-150 g) were divided into four groups of five rats each. Group I (control) was given normal saline (0.6 mL/kg) and group II was given L-NAME (40 mg/kg) for 6 weeks. Groups Ill and IV also received L-NAME (40 mg/kg) for 6 weeks but were further co-treated with 100 and 200 mg/kg of ALETP, respectively, from week 4 to week 6. All treatments were given orally. Strips of corpus cavernosum from each of the four groups were exposed to increasing concentrations of acetyl~ choline (ACh) and sodium nitroprusside (SNP) (10^-9-10^-5 tool/L) after contraction with phenylephrine (10^-7 mol/L) to test for a dose-response effect, Response to potassium and calcium was also measured after cumulatively adding potassium and calcium (10-50 mmol/L) to potassium- and calcium-free organ chamber. Isometric contractions were recorded through an Ugo Basile data capsule acquisition system. Results: Mean arterial blood pressure was significantly reduced in the ALETP co-treated group compared to the control and L-NAME-only groups (P 〈 0.05). Cavernosa strips from ALETP co-treated rats exhibited significant inhibition of contraction in response to phenylephrine, potassium chloride, and calcium chlo- ride (P 〈 0.05). Relaxation in response to Ach and SNP was also significantly impaired in cavernosa strips from the L-NAME-only treated group (P 〈 0.05), while ALETP co-treated groups showed enhanced per- centage relaxation. Conclusion: ALETP treatment of L-NAME-induced hypertensive rats promotes a relaxant effect on isolated cavernosa strips. ALETP shows potential in correcting erectile dysfunction in hypertension.