The effects of androgen on penile reflex, erectile response to electrical stimulation and penile NOS activity in the rat

Aim: To investigate the effects of androgen on penile erection through the reflex arc and penile corpus cavernosum,and study the respective roles of testosterone (T) and dihydrotestosterone (DHT) in penile erection in rats. Methods:Male Sprague-Dawley rats were castrated and implanted with silastic brand silicone tube containing T or DHT, with orwithout daily injections of a 5α-reductase inhibitor, MK-434. The penile reflex, erectile response to electrical stimula-tion (ES) of the cavernous nerves and penile nitric-oxide synthase (NOS) activity were observed under varying andro-genic status. Results: Penile reflex erection in the rat was, on the whole, related to serum T levels though the numberof glans engorgements was not. The number of cups and flips was significantly decreased by castration, and restoredto the control level by T supplementation. Erectile response to ES and NOS activity in penile tissue was also related toserum T level. T administered together with a 5α-reductase inhibitor no longer restored the number of reflex erection,erectile responses to ES and NOS activity in the corpus cavernosum. Conclusion: Androgen influenced the penile re-flex arc, corpus cavernosum, and the perineal striated muscles. In reflex erection, erectile response to ES and penileNOS activity in the rat, T seems to be first converted to DHT, the more active androgen modality. (Asian J Androl1999 Dec; 1: 169-174)

Chronic prostatitis in Korea:a nationwide postal survey of practicing urologists in 2004

Aim： To examine the diagnosis and treatment of chronic prostatitis by means of a nationwide postal survey of practicing urologists in 2004. Methods： A random sample of 850 Korean urologists from the Korean Urological Association Registry of Physicians were asked to complete a questionnaire that explored practicing characteristics, attitudes and diagnostic and treatment strategies in the management of chronic prostatitis. Results： Of the 850 questionnaires sent, 302 were returned （response rate 35.5 %） and 275 were induced in the final analysis. More than 50 % believed in a multifactorial etiology for chronic prostatitis and 52 % considered chronic abacterial prostatitis to be bacterial in nature. For routine diagnostic assessment, the most commonly used tests were reported to be urinalysis （95.3 %）, analysis of expressed prostatic secretions （89.5 %） and digital rectal examination （81.1%）. Only a few urologists use specific lower urinary tract cultures. Symptom assessment according to the National Institute of Health-Chronic Prostatitis Symptom Index was less frequently used （12.7 %）. First choices for therapy included antibiotics （96.4 %）, alpha-blockers （71.6 %） and sitz baths （70.5 %）. If unsuccessful, urologists frequently continued to prescribe a second course of either alpha-blockers （69.5 %） or antibiotics （57.8 %）. Conclusion： These data provide a picture of current practice regarding the management of chronic prostatitis in Korea. The diagnostic and treatment practices for prostatitis do not follow standard textbook algorithms. Further studies are needed to elucidate the etiology and pathogenesis of chronic prostatitis and to establish guidelines for its diagnosis and treatment.

Studies on self-esteem of penile size in young Koreanmilitary men

Aim: To investigate the flaccid and stretched penile sizes of young Korean men and their complexes or pride about their penile size. Methods: After an explanation and agreement to the purpose and methods of this study, 123 Korean men in their early 20's visiting the Jinhae Military General Hospital were included in the study. The flaccid penile length, flaccid mid-shaft circumference, stretched length and pre-pubic bone fat pad depth were measured in a warm comfortable environment. The accuracy the subjects assessed their penile size was investigated by asking them to rate their penile size, as 'very small', 'small', 'normal', 'large' or 'very large'. All subjects were asked to complete the Minnesota multiphasic personality inventory (MMPI) test. Results: The mean flaccid length, flaccid circumference, stretched length and fat pad depth of the 123 subjects were (6.9 ± 0.8) cm, (8.5 ±1.1) cm, (9.6 ± 0.8) cm and (1.1 ± 0.4) cm, respectively. The answer distribution on penile size was 1 (0.8 %) 'very small', 29 (23.6 %) 'small', 86 (69.9 %) 'normal', 6 (4.9 %) 'large' and 1 (0.8 %) 'very large'. Subjects who underestimated their penile size showed significantly higher scores on the hypochondriasis (Hs), depression (D) and psychasthenia (Pt) subscales of the MMPI than those in the Unbiased Group (P<0.05). Conclusion: In consultation, with a patient requesting penile augmentation, the urologist should consider the psychologic attitude of the patient to his penile size.

Serum prostate-specific antigen value adjusted for non-cancerous prostate tissue volume in patients undergoing radical prostatectomy： a new predictor of biochemical recurrence in localized or locally advanced prostate cancer

The aim of this study was to investigate the significance of serum prostate-specific antigen （PSA） value adjusted for total tumor volume （PSA/tumor volume） and serum PSA value adjusted for non-cancerous prostate tissue volume （NCPV） （PSA/NCPV） as a predictor of pathological findings and clinical outcome after radical prostatectomy. Clinical and pathological data of 407 patients （median age： 66.5 years; range： 41.8--85.7 years） were reviewed retrospectively. The median follow-up period was 18. I months （range： 1.0- 107.8 months）. Biochemical recurrence was defined as detectable PSA levels （greater than 0.2 ng ml-1） and the time of biochemical recurrence was taken to be the first time PSA became detectable. In the multivariate model, PSA/NCPV was an independent predictor of extracapsular extension and positive surgical margin （P〈O.05）, but PSA/tumor volume was not. Kaplan-Meier curves revealed that PSA/NCPV correlated with biochemical recurrence-free survival （P〈O.O01; log-rank test） but PSA/tumor volume did not （P=0.275; log-rank test）. PSA/NCPV was also a significant independent prognostic factor for biochemical recurrence-free survival on multivariate Cox proportional hazard analysis （P=0.004, relative risk=2.42）. Our findings suggest that PSA/NCPV is associated independently with extracapsular extension and surgical margin status and may be an independent prognostic variable of PSA recurrence after radical prostatectomy.

Second to fourth digit ratio： a predictor of adult penile ength

The second to fourth digit ratio （2D：4D） has been proposed as a putative biomarker for prenatal testosterone and covaries with the sensitivity of the androgen receptor （AR）. Both prenatal testosterone and the AR play a central role in penile growth. In this study, we investigated the relationship between digit ratio and penile length. Korean men who were hospitalized for urological surgery at a single tertiary academic centre were examined in this study, and 144 men aged 20 years or older who gave informed consent were prospectively enrolled. Right-hand second- and fourth-digit lengths were measured by a single investigator prior to measurement of penile length. Under anaesthesia, flaccid and stretched penile lengths were measured by another investigator who did not measure nor have any the information regarding the digit lengths. Univariate and multivariate analysis using linear regression models showed that only height was a significant predictive factor for flaccid penile length （univariate analysis： r=0. 185, P=-0.026; multivariate analysis： r=-0.172, P=0.038） and that only digit ratio was a significant predictive factor for stretched penile length （univariate analysis： r=-0.216, P=0.009; multivariate analysis： r=-0.201, P=0.024; stretched penile length=-9.201 xdigit ratio ＋ 20.577）. Based on this evidence, we suggest that the digit ratio can predict adult penile size and that the effects of prenatal testosterone may in part explain the differences in adult penile length.

Are age, anthropometry and components of metabolic syndrome-risk factors interrelated with lower urinary tract symptoms in patients with erectile dysfunction？ A prospective study

Aim： To evaluate the effects of metabolic profiles on lower urinary tract symptoms （LUTS） in men with erectile dysfunction （ED）. Methods： A total of 75 impotent men aged 25-75 years old （mean 58.1 years） were included in the study on a prospective basis. Patients were evaluated with a complete history, physical examination, anthropometry and metabolic profiles. LUTS were assessed using the International Prostate Symptom Score （IPSS）. Results： Overall, there was no correlation between the IPSS and continuous parameters. However, when continuous variables were categorized, some parameters were significantly associated with LUTS. Patients with triglyceride level of 150 mg/dL or higher had more severe symptoms than those with tiglyceride levels less than 150 mg/dL （19.4±2.4 vs. 14.3±1.1, P = 0.033）. When 40 mg/dL was chosen as the high-density lipoprotein （HDL）-cholesterol cut-off level, the IPSS was significantly different between the two groups divided by 40 mg/dL （19.4±2.6 for HDL-cholesterol 〈 40 mg/dL vs. 14.4±1.0 for HDL-cholesterol 2 40 mg/dL, P = 0.042）. The area under the receiver operating characteristic curve （AUROCC） of triglyceride was 65.7% （95% confidence interval [CI], 52.6%-82.3%; P = 0.034） for severe LUTS. However, the AUROCC for ＇HDL-cholesterol＇ was not significant （area, 65.4%; 95% CI, 48.2%-82.7%; P = 0.062）. No other factors were determined to be significant in this regard. Conclusion： The results of the present study indicate that some metabolic profiles might influence LUTS in men with ED.

Reasons for discontinuation of sildenafil citrate after successful restoration of erectile function

Aim: To investigate the reasons for discontinuations of sildenafil after the successful restoration of erectile function. Methods: One hundred fifty six patients, whose scores of erectile function domain of the 15-item International Index of Erectile Function (IIEF) increased to 26 or more after sildenafil medication, were included in this study. Six-months after the first sildenafil prescription, compliance to medication and the reason for discontinuity were reviewed by chart or surveyed by telephone. Results: Fifty-four (34.6%) of the 156 successfully treated patients discontinued sildenafil medication. The r easons for discontinuance were shortcomings in the partners' or patients' emotional readiness for the restoration of sexual life after long-term abstinence (37.0%), fear of possible side effects (18.5 %), recovery of spontaneous erection (14.8 %), postponement of ED treatment because of co morbid disease treatment (11.1%), unwillingness to accept drug-dependent erection (7.4%), high drug cost (3.7%), unacceptability of planned sexual activity (3.7%) and lack of sexual interesi (3.7%). Conclusion: The reasons for discontinuing sildenafil medication were primarily emotional or relationship-oriented, which indicates that simple recovery of a rigid erection is insufficient to restore sexual activity. More education about the effects of drug and the counseling of both partners is recommended to promote the successful recovery of sexual activity.

Potentiation of apomorphine effect on sildenafil-induced penile erection in conscious rabbits

Aim: To investigate a possible potentiation effect of apomorphine (APO) on sildenafil-induced penile erection in the conscious rabbit. Methods: Erection of male New Zealand White rabbits (3.5-4.0 kg, n=12) was assessed by measuring the length of the uncovered penile mucosa and the duration of erection before and after intravenous administration of agents. After injection of APO (0, 0.05, 0.1 and 0.4 mg/kg), sildenafil was administered intravenously in a dose-response manner (0.5, 1 and 5 mg/kg). In additional experiments, the effect of increasing doses of sildenafil in combination with APO on systemic blood pressure was evaluated. Results: Systemic administration of sildenafil induced a dose-dependent increase in the penile length. Intravenous injection of APO alone did not produce any change in the penile length, while significantly enhanced the penile erection induced by sildenafil. The co-administration of 0.1 mg/kg of APO and 1 mg/kg of sildenafil was found to be the most effective combination in producing penile erection. Intravenous administration of sildenafil caused a concentration-dependent decrease in systemic blood pressure, but no additional decrease was observed with co-administration of APO. Conclusion: APO enhances the penile erection induced by sildenafil in the conscious rabbit without causing an additional decrease in blood pressure.

The learning curve for transurethral enucleation with bipolar energy for benign prostate hyperplasia:a single-surgeon experience of 494 patients

This study was performed to investigate the learning curve of transurethral enucleation with bipolar energy(TUEB)for benignprostatic hyperplasia.The study involved 494 consecutive patients who underwent TUEB for benign prostatic hyperplasia fromAugust 2018 to March 2022 by one surgeon(SJJ,Seoul National University Bundang Hospital,Seongnam,Korea).The patientswere followed up at 1 week,1 month,3 months,and 6 months postoperatively.To evaluate the learning curve of TUEB,perioperativeparameters including the enucleation ratio(enucleated tissue weight/transitional zone volume),TUEB efficiency(enucleatedtissue weight/operation time),and enucleation efficiency(enucleated tissue weight/enucleation time)were analyzed.Functionaloutcomes and postoperative complications were also assessed,including the International Prostate Symptom Score(IPSS),IPSSquality-of-life(QoL)score,and uroflowmetry outcomes.The patients’median age was 72(interquartile range[IQR]:66–78)years,and the estimated prostate volume and transitional zone volume were 63.0(IQR:46.0–90.6)ml and 37.1(IQR:24.0–60.0)ml,respectively.The enucleation ratio,TUEB efficiency,and enucleation efficiency were 0.60(IQR:0.46–0.54)g ml−1,0.33(IQR:0.22–0.46)g min−1,and 0.50(IQR:0.35–0.72)g min−1,respectively,plateauing after 70 cases.The functional outcomes,including total IPSS,IPSS QoL score,and uroflowmetry outcomes,significantly improved at 6 months after TUEB(all P<0.05),but without significant differences over the learning curve.Sixty-five(13.2%)patients developed complications after TUEB,21.5%of whom experienced major complications(Clavien–Dindo grade≥3).The rate of major complications declined as the number ofTUEB cases increased(P=0.013).Our results suggest that the efficiency of TUEB stabilized within 70 procedures.

Role of inhibiting LIM-kinase2 in improving erectile function through suppression of corporal fibrosis in a rat model of cavernous nerve injury

We evaluated whether LIM-kinase 2 inhibitor （LIMK2i） could improve erectile function by suppressing corporal fibrosis through the normalization of the Rho-associated coiled-coil protein kinase 1 （ROCK1）/LIMK2/Cofilin pathway in a rat model of cavernous nerve crush injury （CNCl）. Sixty 11-week-old male Sprague-Dawley rats were divided equally into five groups： sham surgery （S）, CNCl （I）, and CNCl treated with low-dose （L）, medium-dose （M）, and high-dose （H） LIMK2i. The L, M, and H groups were treated with a daily intraperitoneal injection of LIMK2i （2.5, 5.0, and 10.0 mg kg-1 body weight, respectively） for 1 week after surgery. The erectile response was assessed using electrostimulation at 1 week, postoperatively. Penile tissues were processed for Masson＇s trichrome staining, double immunofluorescence, and Western blot assay. Erectile responses in the H group improved compared with the I group, while the M group showed only partial improvement. A significantly decreased smooth muscle/collagen ratio and an increased content of fibroblasts positive for phospho-/IMK2 were noted in the I group. The M and H groups revealed significant improvements in histological alterations and the dysregulated LIMK2/Cofilin pathway, except for LIMK2 phosphorylation in the M group. The inhibition of LIMK2 did not affect the ROCK1 protein expression. The content of fibroblasts positive for phospho-LIMK2 in the H group returned to the level found in the S group, whereas it did not in the M group. However, the L group did not exhibit such improvements. Our data suggest that the inhibition of LIMK2, particularly with administration of 10.0 mg kg^-1 body weight LIMK2i, can improve corporal fibrosis and erectile function by normalizing the LIMK2/Cofilin pathway.

The effects of single versus combined therapy using LIM-kinase 2 inhibitor and type 5 phosphodiesterase inhibitor on erectile function in a rat model of cavernous nerve injury-induced erectile dysfunction

We aimed to determine whether combination of LIM-kinase 2 inhibitor(LIMK2i)and phosphodiesterase type-5 inhibitor(PDE5i)could restore erectile function through suppressing cavernous fibrosis and improving caver nous apoptosis in a rat model of cavernous nerve crush injury(CNCI).Seventy 12-week-old Sprague-Dawley rats were equally distributed into five groups as follows:(1)sham surgery(Group S),(2)CNCI(Group I),(3)CNCI treated with daily intraperitoneal administration of 10.0 mg kg^-1 LIMK2i(Group I+L),(4)daily oral administration of 20.0 mg kg-1 udenafil,PDE5i(Group I+U),and(5)combined administration of 10.0 mg kg^-1 LIMK2i and 20.0 mg kg^-1 udenafil(Group I+L+U).Rats in Groups I+L,I+U,and I+L+U were treated with respective regimens for 2 weeks after CNCI.At 2 weeks after surgery,erectile response was assessed using electrostimulation.Penile tissues were processed for histological studies and western blot.Group I showed lower intracavernous pressure(ICP)/mean arterial pressure(MAP),lower area under the curve(AUC)/MAP,decreased immunohistochemical staining for alpha-smooth muscle(SM)actin,higher apoptotic index,lower SM/collagen ratio,increased phospho-LIMK2-positive fibroblasts,decreased protein kinase B/endothelial nitric oxide synthase(Akt/eNOS)phosphorylation,increased LIMK2/cofilin phosphorylation,and increased protein expression of fibronectin,compared to Group S.In all three treatment groups,erectile responses,protein expression of fibronectin,and SM/collagen ratio were improved.Group I+L+U showed greater improvement in erectile response than Group I+L.SM content and apoptotic index in Groups I+U and I+L+U were improved compared to those in Group I.However,Group I+L did not show a significant improvement in SM content or apoptotic index.The number of phospho-LIMK2-positive fibroblasts was normalized in Groups I+L and I+L+U,but not in Group I+U.Akt/eNOS phosphorylation was improved in Groups I+U and I+L+U,but not in Group I+L.LIMK2/cofilin phosphorylation was improved in Groups I+L and I+L+U,but not in Group I+U.Our data indicate that combined treatment of LIMK2i and PDE5i immediate after CN injury could improve erectile function by improving cavernous apoptosis or eNOS phosphorylation and suppressing cavernous fibrosis.Rectification of Akt/eNOS and LIMK2/cofilin pathways appears to be involved in their improvement.

Outcomes of men aged≤50 years treated with radical prostatectomy:a retrospective analysis

Previous studies inv estigating prostate can cer(PCa)features in youn ger men have reported con flicting fin dings.This study aimed to investigate pathologic outcomes and biochemical recurrenee(BCR)status in younger men who underwent radical prostatectomy(RP)for PCa.Records of 2057 patients who underwent RP at Seoul National University Bundang Hospital(Seongnam,Korea)between 2006 and 2015 were reviewed;patients were divided according to age into the younger and older groups(men aged<50 and>50 years,respectively).Postoperative BCR status and functional outcomes and clinicopathologic features were compared betwee n both groups.All an alyses were repeated after propensity score matchi ng.Younger men were more likely to have lowrisk disease(P<0.001),lower pathologic Gleason score(P<0.001)and pathologic stages(P<0.001)than older men.The pathologic Gleason score(P=0.002)and rates of extracapsular extension(P=0.004)were lower in younger men after propensity score matching.In multivariate analysis,age at RP was not an independent predictor of BCR-free survival after RP(P=0.669).Moreover,at 1 year after RP,younger men with preoperative 5?item International Index of Erectile Function score≥22(n=228)showed more favorable results for urinary con tine nee(defi ned as nonuse of pads daily)(99.4%vs 95%,P=0.009)and erections sufficie nt for vaginal in tercourse(81.8%vs 55.5%,P=0.001).Youn ger men had more favorable clinicopathologic features at RP than their older counterparts.Although age was not an independent predictor of BCR status outcome,younger men had better functional outcomes following RP.