Study on mitochondrial DNA diversity among 7 inbred strains of mice

Objective: To study the genetic variation of mitochondrial DNA(mtDNA) among common laboratory strains of inbred mice. Methods: The genetic polymorphism of mtDNA among 4 classical laboratory strains of inbred mice and 3 inbred strains of mice established in China was analyzed by polymerase chain reaction coupled with restriction fragment length polymorphism(PCR-RFLP) and PCR coupled with single-stranded conformation polymorphism(PCR-SSCP). Results: With regard to the D-loop(Displacement loop,D-loop),tRNAMet+Glu+(?)e,and ND3(NADH dehydrogenase subunit 3,ND3) gene fragments of mtDNA from these mice,no variation was revealed by PCR-RFLP at 46 restriction enzyme sites. Further analyzed by PCR-SSCP,the D-loop 5'fragment and 3'end fragment of mtDNA from these mice also showed no genetic variation. Conclusion: Owing to maternal mode of inheritance of mtDNA,the results indicate that these common inbred strains of mice share the same maternal lineage.

Regular nicotine intake increased tooth movement velocity,osteoclastogenesis and orthodontically induced dental root resorptions in a rat model

Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further （side） effects can be expected during orthodontic treatment at a nicotine exposure corresponding to that of an average European smoker. 63 male Fischer344 rats were randomized in three consecutive experiments of 21 animals each （A/B/C） to 3 experimental groups （7 rats, 112/3）. （A） cone-beam-computed tomography （CBCT）; （B） histology/serology; （C） reverse- transcription quantitative real-time polymerase chain reaction （RT-qPCR）/cotinine serology--（1） control; （2） orthodontic tooth movement （OTM） of the first and second upper left molar （NiTi closed coil spring, 0.25 N）; （3） OTM with 1.89 mg-kg- 1 per day s.c. of L（- ）-nicotine. After 14 days of OTM, serum cotinine and IL-6 concentration as well as orthodontically induced inflammatory root resorption （OIIRR）, osteoclast activity （histology）, orthodontic tooth movement velocity （CBCT, within 14 and 28 days of OTM） and relative gene expression of known inflammatory and osteoclast markers were quantified in the dental-periodontal tissue （RT-qPCR）. Animals exposed to nicotine showed significantly heightened serum cotinine and IL-6 levels corresponding to those of regular European smokers. Both the extent of root resorption, osteoclast activity, orthodontic tooth movement and gene expression of inflammatory and osteoclast markers were significantly increased compared to controls with and without OTM under the influence of nicotine. We conclude that apart from increased periodontal bone loss, a progression of dental root resorption and accelerated orthodontic tooth movement are to be anticipated during orthodontic therapy, if nicotine consumption is present. Thus patients should be informed about these risks and the necessity of nicotine abstinence during treatment.

Changes of phasic and tonic smooth muscle function of jejunum in type 2 diabetic Goto-Kakizaki rats

AIM:To generate phasic and tonic stress-strain curves for evaluation of intestinal smooth muscle function in type 2 diabetic rats during active and passive conditions.METHODS:Seven diabetic Goto-Kakizaki(GK)male rats,32-wk old(GK group),and 9 age-matched normal Wistar rats(Normal group)were included in the study.Jejunal segments were distended up to a pressure of10 cm H2O in an organ bath containing 37℃Krebs solution with addition of carbachol(CA).The pressure and outer diameter changes were synchronously recorded.Passive conditions were obtained using calcium-free Krebs solution containing ethylene glycol tetraacetic acid and papaverine.Total phasic,tonic and passive circumferential stress and strain were computed from the diameter and pressure data with reference to the zero-stress state geometry.The active phasic and tonic stresses were defined as the total phasic and tonic stresses minus the passive stress.RESULTS:Diabetes increased jejunal mucosa and muscle layer thicknesses compared to the Normal group(mucosa,755.8±63.3 vs 633.1±59.1μm,P<0.01;muscle,106.3±12.9 vs 85.2±11.7μm,P<0.05).The pressure and stress thresholds were decreased in the GK group after CA application compared to distensions without CA application(pressure,1.01±0.07vs 1.99±0.19 cmH2O,P<0.01;stress,0.11±0.01vs 0.24±0.02 kPa,P<0.01).CA application did not change the pressure and stress threshold in the Normal group(pressure,2.13±0.32 vs 2.34±0.32 cm H2O,P>0.05;stress,0.25±0.03 vs 0.35±0.06 kPa,P>0.05).The amplitude of total phasic,total tonic,active phasic and active tonic circumferential stresses did not differ for the distensions without CA application between the GK group and the Normal group.However,the total phasic and total tonic stresses increased after CA application in the GK group compared those in the Normal group.When normalized to muscle layer thickness,the amplitude of active stresses before CA application was lowest in the GK group compared with the Normal group.No difference was found during CA application.CONCLUSION:The stress generated by intestinal muscle normalized to the muscle layer thickness was lowest in GK rats compared to normal rats whereas the response to CA stimulation was preserved.

Integrative rodent models for assessing male reproductive toxicity of environmental endocrine active substances

In the present review, we first summarize the main benefits, limitations and pitfalls of conventional in vivo approaches to assessing male reproductive structures and functions in rodents in cases of endocrine active substance （EAS） exposure from the postulate that they may provide data that can be extrapolated to humans. Then, we briefly present some integrated approaches in rodents we have recently developed at the organism level. We particularly focus on the possible effects and modes of action （MOA） of these substances at low doses and in mixtures, real-life conditions and at the organ level, deciphering the precise effects and MOA on the fetal testis. It can be considered that the in vivo experimental EAS exposure of rodents remains the first choice for studies and is a necessary tool （together with the epidemiological approach） for understanding the reproductive effects and MOA of EASs, provided the pitfalls and limitations of the rodent models are known and considered. We also provide some evidence that classical rodent models may be refined for studying the multiple consequences of EAS exposure, not only on the reproductive axis but also on various hormonally regulated organs and tissues, among which several are implicated in the complex process of mammalian reproduction. Such models constitute an interesting way of approaching human exposure conditions. Finally, we show that organotypic culture models are powerful complementary tools, especially when focusing on the MOA. All these approaches have contributed in a combinatorial manner to a better understanding of the impact of EAS exposure on human reproduction.

Diet and Rat Strain as Factors in Nervous System Function and Influence of Confounders

The necessity for understanding normal human cognitive processes and behavior, and themechanisrns which result in dysfunction in these processes are dependant on utilization of a suitable animal model. In order to develop pharmaceutical agents to alleviate mental disturbances and enable the individual to cope within the norms of society, it is incumbent upon investigators to choose a species in which pharmacokinetic principles are established and resemble those of hurnans. The choice of rats in cognition research studies has specific advantages in that these anirnals possess similar pharrnacodynamic parameters to hurnans. Further advantages include availability, low cost, ease of breeding, maintenance and an extensive literature database which enable comparisons to present findings. However, there are substantial differences in the perforrnance of various rat strains in tasks of learning, memory, attention, and responses to stress or drugs. In addition to rat strain, quantity of thed also exerts profound consequences on animal behavior. The aim of this review is to demonstrate that there are differences in the central nervous systern responsivencess of rat strains to chemicals and these could be related to factors such as source of supplier, type and quantity of feed, or season of the year. It is also evident that the genotype differs amongst strains and this may be responsible for the observed differences in CNS sensitivity to chemicals. Strain differences must be identified and taken into consideration in interpretation of assessrnent of neurobehavioural functions. It is also incumbent upon the investigators to utilize healthy (diet-controlled) animal models.

Effect of Kaiyu Qingwei Jianji on the morphometry and residual strain distribution of small intestine in experimental diabetic rats

AIM: To investigate the effect of a Chinese medicine, Kaiyu Qingwei Jianji (KYQWJJ) used for diabetic treatment, on the morphometry and residual strain distribution of the small intestine in streptozotocin (STZ) -induced diabetic rats. Correlation analysis was also performed between the opening angle and residual strain with the blood glucose level. METHODS: Forty-two male Wistar rats weighing 220-240 g were included in this study. Thirty-two STZ- induced diabetic rats were subdivided into four groups (n = 8 in each group), i.e. diabetic control group (DM); high dose of KYQWJJ (T1, 36g/kg per day); low dose of KYQWJJ (T2, 17 g/kg per day) and Gliclazide (T3, 50 mg/kg per day). Another ten rats were used as non- diabetic control (CON). The medicines were poured directly into stomach lumen by gastric lavage twice daily. The rats of CON and DM groups were only poured the physiological saline. Blood glucose and plasma insulin levels were measured. Experimental period was 35 d. At the end of experiment, three 5-cm long segments were harvested from the duodenum, jejunum and ileum. Three rings of 1-2 mm in length for no-load and zero-stress state tests were cut from the middle of different segments. The morphometric data, such as the circumferential length, the wall thickness and the opening angle were measured from the digitized images of intestinal segments in the no-load state and zero- stress state. The residual strain was computed from the morphometry data. Furthermore, the linear regressionanalysis was performed between blood glucose level with morphometric and biomechanical data in the different intestinal segments. RESULTS: The blood glucose level of DM group was consistent 4-fold to 5-fold higher than those in CON group during the experiment (16.89 ± 1.11 vs 3.44 ± 0.15 mmol/L, P < 0.001). The blood glucose level in the T1 (16.89 ± 1.11 vs 11.08 ± 2.67 mmol/L, P < 0.01) and T3 groups (16.89 ± 1.11 vs 13.54 ± 1.73 mmol/L, P < 0.05), but not in T2 group (P > 0.05) was significantly lower than those in DM group. The plasma insulin levels of DM, T1, T2 and T3 groups were significantly lower than those in CON group (10.98 ± 1.02, 12.52 ± 1.42,13.54 ± 1.56,10.96 ± 0.96 vs 17.84 ± 2.34 pmol/L respectively, P < 0.05), but no significantly difference among the groups with exception of CON group. The wet weight/cm and total wall thickness of duodenum, jejunum and ileum in DM group were significantly higher than those in CON group (wet weight (g/cm): duodenum 0.209 ± 0.012 vs 0.166 ± 0.010, jejunum 0.149 ± 0.008 vs 0.121 ± 0.004, ileum 0.134 ± 0.013 vs 0.112 ± 0.007; Wall thickness (mm): duodenum 0.849 ± 0.027 vs 0.710 ± 0.026, jejunum 0.7259 ± 0.034 vs 0.627 ± 0.025, ileum 0.532 ± 0.023 vs 0.470 ± 0.010, all P < 0.05), T1 and T3 treatment could partly restore change of wall thickness, but T2 could not. The opening angle and absolute value of inner and outer residual stain were significantly smaller in duodenal segment (188 ± 11 degrees, -0.31 ± 0.02 and 0.35 ± 0.03 vs 259 ± 15 degrees, -0.40 ± 0.02 and 0.43 ± 0.05) and larger in jejunal (215 ± 20 degrees, -0.30 ± 0.03 and 0.36 ± 0.06 vs 172 ± 19 degrees, -0.25 ± 0.02 and 0.27 ± 0.02) and ileal segments (183 ± 20 degrees, -0.28 ± 0.01 and 0.34 ± 0.05 vs 153 ± 14 degrees, -0.23 ± 0.03 and 0.29 ± 0.04) in DM group than in CON group (P < 0.01). T1 and T3 treatment could partly restore this biomechanical alteration, but strong effect was found in T1 treatment (duodenum 243 ± 14 degrees, -0.36 ± 0.02 and 0.42 ± 0.06, jejunum 180 ± 15 degrees, -0.26 ± 0.03 and 0.30 ± 0.06 and ileum 163 ± 17 degrees, -0.23 ± 0.03 and 0.30 ± 0.05, compared with DM, P < 0.05). The linear association was found between the glucose level with most morphometric and biomechanical data. CONCLUSION: KYQWJJ (high dose) treatment could partly restore the changes of blood glucose level and the remodeling of morphometry and residual strain of small intestine in diabetic rats. The linear regression analysisdemonstrated that the effect of KYQWJJ on intestinal opening angle and residual strain is partially through its effect on the blood glucose level.

Intravenous administration of glutathione protects parenchymal and non-parenchymal liver cells against reperfusion injury following rat liver transplantation

AIM:To investigate the effects of intravenous administration of the antioxidant glutathione (GSH) on reperfusion injury following liver transplantation.METHODS:Livers of male Lewis rats were transplanted after 24 h of hypothermic preservation in University of Wisconsin solution in a syngeneic setting. During a 2-h reperfusion period either saline (controls,n=8) or GSH (50 or 100μmol/(h·kg),n=5 each) was continuously administered via the jugular vein.RESULTS:Two hours after starting reperfusion plasma ALT increased to 1 457±281U/L (mean±SE) in controls but to only 908_+187 U/L (P<0.05) in animals treated with 100μmol GSH/(h·kg).No protection was conveyed by 50μmol GSH/(h·kg).Cytoprotection was confirmed by morphological findings on electron microscopy:GSH treatment prevented detachment of sinusoidal endothelial cells (SECs) as well as loss of microvilli and mitochondrial swelling of hepatocytes. Accordingly, postischemic bile flow increased 2-fold. Intravital fluorescence microscopy revealed a nearly complete restoration of sinusoidal blood flow and a significant reduction of leukocyte adherence to sinusoids and postsinusoidal venules. Following infusion of 50μmol and 100 μmol GSH/(h·kg),plasma GSH increased to 65±7mol/L and 97±18μmol/L,but to only 20±3mol/L in untreated recipients.Furthermore, plasma glutathione disulfide (GSSG) increased to 7.5±1.0mol/L in animals treated with 100μmol/(h·kg) GSH but infusion of 50μmol GSH/(h·kg) did not raise levels of untreated controls (1.8±0.5mol/L vs 2.2±0.2mol/L).CONCLUSION:Plasma GSH levels above a critical level may act as a “sink” for ROS produced in the hepatic vasculature during reperfusion of liver grafts.Therefore, GSH can be considered a candidate antioxidant for the prevention of reperfusion injury after liver transplantation, in particular since it has a low toxicity in humans.

High IFN-α expression is associated with the induction of experimental autoimmune uveitis (EAU) in Fischer 344 rat

Th1-response plays a crucial role in determining pathogenesis of organ-specific autoimmune diseases. It is believed that both IL-12 and INF-a are initiators to regulate Th1-response. In our experimental autoimmune uveitis (EAU) model, both Lewis and Fischer 344 rats share the same MHC class II molecules, while Lewis rat is EAU susceptible and Fischer 344 rat is EAU resistant. However, under the same condition of immunization, if pertussis toxin (PTX) was injected intraperitoneally as an additional adjuvant, Fischer 344 rat can develop EAU. In this study we investigate which mechanisms are involved in the induction of EAU in CFA + R16 + PTX treated (CRP- treated) Fischer 344 rats. In vivo and in vitro data demonstrated that Th1-cytokine, IFN- mRNA expression was significantly increased in disease target tissue-eyes and in draining lymph node cells of CRP-treated Fischer 344 rat. When IL-12 and IFN-a mRNA expression were compared in the experimental groups, only IFN-a mRNA expression was associated with EAU development. To distinguish the sources of IFN-a producing cells, it was observed that IFN-a expression was mainly produced by macrophages. It was further confirmed that normal macrophage from Fischer 344 rat was able to produce significant IFN-a in the presence of PTX. The data strongly suggested that IFN-a might be involved in initiating Th1-cell differentiation and in turn contribute to the induction of EAU. High IFN-a expression induced by PTX may represent a novel pathway to initiate Th1 response in Fischer 344 rat.

Opening angles and residual strains in normal rat trachea

The no-load state and zero-stress state of the normal rat trachea were analyzed. It was found that there exist compressive residual strains in the inner wall region of the rat trachea and tensile residual strains in the outer wall region. The fact that the opening angle of the rat trachea cut at the cartilaginous region is significantly larger than that cut at the muscular portion shows that residual strains exist mainly in the muscular region in the rat trachea. It was also indicated that the opening angles and residual strains expressed by cutting at the muscular portion are basically identical along longitudinal location and those expressed by cutting in the cartilaginous region tend to increase in the longitudinal direction in the normal rat, and that there exists quantitatively positive correlation between the opening angles and residual strains in rat trachea. The results will help to further understand the opening angles and residual strains in the trachea and study tracheal remodeling in response to mechanical environment.

Tong-xin-luo capsule inhibits left ventricular remodeling in spontaneously hypertensive rats by enhancing PPAR-γ expression and suppressing NF-κB activity

Background Tong-xin-luo capsule （TXL）, used as a traditional Chinese herb, offeres a therapeutic potential for treatment of cardiovascular diseases. It has been shown to exert a variety of pharmacological effects, including antihypertensive effects, and is able to improve ventricular remodeling. However, the mechanisms of its action are not completely understood. The aim of this study was to evaluate the molecular mechanisms of Tong-xin-luo capsule on left ventricular remodeling in spontaneously hypertensive rats （SHR）. Methods Sixteen eight-week-old SHRs were randomized into an SHR group （n=8） and a TXL group （n=8） that were given Tong-xin-luo capsule （1.5 mg·kg^-1·d^-1）. Eight Wistar Kyoto （WKY） rats fed with 0.9% NaCl served as the control group （WKY group）. Systolic blood pressure （BP）, body weight and heart rate were monitored once every two weeks. Ventricular remodeling was detected by histopathological examination. Nuclear factor kappa B P65 （NF-κB P65） and peroxisome proliferators activated receptor y （PPAR-γ） protein and phosphorylated inhibitor kappa a （IκBα） protein were detected by immunohistochemistry and western blot respectively. The physical interaction of the P65-P50 heterodimer with IκBα and NF-κB were measured by co-immunoprecipitation. PPAR-γ mRNA, collagen Ⅰ mRNA and collagen Ⅲ mHNA were measured by real-time PCR.Results TXL inhibited NF-κB P65 expression and ventricular remodeling and suppressed the activation of NF-κB compared with the SHR group （P〈0.01, P〈0.05）. TXL reduced IκBα phosphorylation, increased expression of PPAR-γ protein and enhanced the physical interaction of the P65-P50 heterodimer with IκBα. The mRNA expression of PPAR-γ was enhanced but the mRNA expression of collagen Ⅰ mRNA and collagen Ⅲ mRNA were suppressed by TXL. Conclusions In spontaneously hypertensive rats, TXL could inhibit ventricular remodeling induced by hypertension, and the inhibitory effect might be associated with the process of TXL increasing the expression of PPAR-γ that could result in the inhibition of the activation of NF-κB.

高频超声在构建SD大鼠皮下移植性乳腺癌模型中的应用

目的:应用MADB-106大鼠乳腺癌细胞悬液皮下移植法建立SD大鼠乳腺癌移植性肿瘤动物模型,并使用高频超声监测肿瘤生长情况。方法:选取7~8周龄雌性SD乳鼠16只,将处于对数生长期的MADB-106大鼠乳腺癌细胞悬液于大鼠腹股沟皮下接种,应用高频超声观察成瘤率、肿块大小、血供情况及其它声像图特征。结果:SD大鼠接种成功率为100%,死亡2只,剩余14只生长良好;超声检查肿块为类圆形,内部低回声且稍不均匀,边界尚清,后方回声衰减,彩色多普勒扫查肿块内部及周边可见较丰富血流信号;3周后切除瘤体组织,大体观肿块成灰白色,多呈椭圆形,部分边缘呈分叶状改变,肿瘤血管较丰富,镜下可见肿瘤细胞大小形状各异,核大深染,异型性明显。结论:通过MADB-106大鼠乳腺癌细胞接种于雌性SD大鼠腹股沟皮下,成功建立了大鼠乳腺癌移植性肿瘤动物模型。高频超声技术可以在SD大鼠乳腺癌皮下成瘤过程中对肿物的大小、形态、边界、内部回声及血流等生物学情况进行动态检测,是观察和评价瘤体动态变化过程的重要技术手段。

PVG大鼠生化标记基因的测定

目的 对PVG大鼠进行生化标记基因的测定。方法 依据国家标准GB/T 14927.1—2008《实验动物近交系小鼠、大鼠生化标记检测法》测定,随机抽取4只PVG大鼠,取(肺、肾、小肠、睾丸)组织器官进行样品制备,用醋酸纤维薄膜电泳法检测11个生化位点(Hbb、Cs1、Alp1、Akp1、Esl、Es3、Es4、Es6、Es8、Es9和Esl0)。结果 PVG大鼠11个位点的基因型分别是Hbb为b型,Cs1为b型,Alp1为b型,Akp1为a型,Esl为a型,Es3为d型,Es4为b型,Es6为b型,Es8为b型,Es9为a型和Esl0为a型,且均为纯合。结论 PVG大鼠遗传生化标记结果符合近交系特征。

Effects of electroacupuncture at Taichong(LR 3) and Baihui(DU 20)on cardiac hypertrophy in rats with spontaneous hypertension

OBJECTIVE: To investigate the effects of electroacupuncture(EA) at Taichong(LR 3) and Baihui(DU 20)on myocardial hypertrophy in spontaneously hypertensive rats(SHRs).METHODS: Thirty-six SHRs were randomly assigned to model, EA, and Losartan groups, with twelve rats per group. Twelve Wistar Kyoto rats were selected as the normal control group. Systolic blood pressure(SBP) and cardiac function were measured in all rats.Expression levels of factors associated with the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/Akt/mTOR) pathway were evaluated by Western blotting and real-time PCR.Pathological changes of the heart tissue were observed by hematoxylin-eosin staining.RESULTS: After treatment, enhanced SBP was significantly decreased in the EA and Losartan groups compared with the model group(P < 0.01). Echocardiographic and morphological analyses revealed that enhanced end-diastolic interventricular septal thickness and left ventricular posterior wall thickness, as well as ratio of left ventricular weight to body weight were markedly diminished in the EA and Losartan groups(P < 0.01 or P < 0.05), while reduced left ventricular end-diastolic dimension and left ventricular ejection fraction were significantly ameliorated(P < 0.01). Real-time PCR and western blotting analyses showed that the expression levels of PI3K,Akt, and mT OR in SHRs were significantly up-regulated by EA and Losartan(P < 0.01), while the expression levels of PTEN and ANP were down-regulated(P < 0.01).CONCLUSION: EA at Taichong(LR 3) and Baihui(DU20) inhibited the development of cardiac hypertrophy and improved the cardiac function in SHRs, possibly through regulation of the PI3K/Akt/mTOR signalling pathway.

Effect of Taichong(LR 3) acupuncture in spontaneously hypertensive rats

OBJECTIVE: To evaluate the effects of Taichong(LR3) acupuncture points(acupoints) on the expression of glucose transporter protein 1(GLUT1) in the hypothalamus of spontaneously hypertensive rats(SHRs) as measured by combined positron emission tomography and computed tomography(PETCT).METHODS: Spontaneously hypertensive rats(SHR)were divided into model, Taichong(LR 3) acupuncture, and sham groups. Additionally, Tokyo Wistar rats were used as the control group. Changes in blood pressure were recorded in different groups of rats before and after the corresponding treatment. Hematoxylin and eosin(HE) staining was used to study basic morphological changes, and immunohistochemistry was used to determine GLUT1 expression in the hypothalamus. Further,PET-CT was utilized to elucidate the antihypertensive mechanism after acupuncture at the Taichong(LR 3) acupoints.RESULTS: PET-CT indicated activation of the hypothalamus. Measurement of blood pressure showed that acupuncture at the Taichong(LR 3) acupoints lowered blood pressure. HE staining did not show any significant pathological changes, although differences in cell number were observed. Immunohistochemical analysis indicated a GLUT1 downregulation in the SHRs of the Taichong(LR 3) acupuncture group after the treatment.CONCLUSION: Acupuncture at Taichong(LR 3) acupoints lowered blood pressure in SHRs, with possible mechanisms being changes in cell number and GLUT1 expression in the hypothalamus.

Upregulation of the angiotensin-converting enzyme 2-angiotensin-(1-7)-Mas receptor axis by a combination of Yinyanghuo(Herba Epimedii Brevicornus) and Cheqianzi(Semen Plantaginis) improves erectile function in spontaneously hypertensive rats

OBJECTIVE:To evaluate the effects of a combination of Yinyanghuo(Herba Epimedii Brevicornus)(HEB)and Cheqianzi(Semen Plantaginis)(SP)on erectile dysfunction caused by essential hypertension in spontaneously hypertensive rats(SHRs),and to elucidate the role of the angiotensin-converting enzyme 2-angiotensin-(1-7)-Mas receptor(ACE2/Ang[1-7]/Mas receptor)axis in this process.METHODS:A total of 24 SHRs were randomly assigned to three groups:SHR-control,low-dose(12.5 g/kg)and high-dose(25 g/kg)HEB+SP(HEBSP).Eight Wistar-Kyoto rats were used as normal controls.HEBSP was administered by oral gavage for 28 d.Erectile function was measured once a week using the Heaton test.After 4 weeks of treatment,the corpus cavernosum was harvested from each rat to measure nitric oxide(NO),nitric oxide synthase(e NOS)and Ang(1-7)levels,as well as ACE2,Mas receptor and neuronal nitric oxide synthase(n NOS)protein expression.RESULTS:After 4 weeks of treatment,HEBSP significantly increased erectile function in the treated group compared with SHR-control group(P<0.01).Additionally,HEBSP treatment significantly increased cavernosal levels of Ang(1-7),e NOS and NO.Moreover,HEBSP significantly elevated the expression levels of ACE2,Mas receptor and n NOS.These beneficial effects were elevated in the high-dose HEBSP group.CONCLUSION:HEBSP improved erectile function in SHRs by upregulating the ACE2/Ang(1-7)/Mas receptor axis,e NOS and n NOS pathways.

Proliferation of aortic smooth muscle cells and renin-angiotensin system in SHR rats

目的：探讨ＳＨＲ大鼠主动脉平滑肌细胞（ＡＳＭＣ）异常增殖和肾素血管紧张素系统（ＲＡＳ）的关系．方法：测定血管紧张素Ｉ（Ａｎｇ）、卡托普利（Ｃａｐ）、沙拉新（Ｓａｒ）对培养的ＳＨＲ、ＷＫＹＡＳＭＣ增殖和Ａｎｇ、血管紧张素转化酶（ＡＣＥ）的影响．结果：Ａｎｇ在２％血清培养基中可刺激ＳＨＲＡＳＭＣ增生．ＳＨＲＡＳＭＣ分裂增殖能力比ＷＫＹ强，ＳＨＲＡＳＭＣＲＡＳ处于高功能状态．Ｃａｐ长期（４周）干预显著抑制ＳＨＲＡＳＭＣ异常增殖和Ａｎｇ、ＡＣＥ活性，Ｓａｒ长期干预同样抑制ＳＨＲＡＳＭＣ的增殖和ＡＣＥ活性，但Ａｎｇ水平反而升高．Ｃａｐ短期（２４小时）干预不影响两种大鼠ＡＳＭＣＲＡＳ．结论：Ｃａｐ和Ｓａｒ长期干预通过减少ＳＨＲＡＳＭＣＡｎｇ生成或阻断Ａｎｇ和特异受体结合，抑制其异常增殖．

复合因素诱导射血分数保留心力衰竭大鼠模型的建立及评价

目的 通过复合因素建立射血分数保留心力衰竭(HFpEF)大鼠模型,评估其特征,并探讨心肌应变参数与心肌肥厚及纤维化的相关性。方法 8只WKY大鼠和8只自发性高血压大鼠(SHR)作为对照组,给予普通饲料至实验结束。32只SHR大鼠平均分SHR+S组、SHR+F组、SHR+SF组及SHR+复合组,分别给予高盐饲料、高脂饲料、高盐-脂饲料、高盐-脂-糖饲料联合腹腔注射链脲霉素30周。造模结束后,测量心重/体重(HW/BW)、收缩压(SBP)及舒张压(DBP);行超声心动图测量左心室(LV)舒张末内径(LVIDd)、LV前壁厚度(LVAWd)、LV后壁厚度(LVPWd)、LV射血分数(LVEF)、等容舒张时间(IVRT)、LV舒张早期二尖瓣流入峰值速度(E)/二尖瓣环运动速度(e’);斑点追踪超声心动图测量全纵向应变(GLS)及应变率(GLSr)、全径向应变(GRS)及应变率(GRSr)、全周向应变(GCS)及应变率(GCSr);血清学检测甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL-C)、葡萄糖(GLU)及糖化血清蛋白(GSP),ELISA法检测血清B型利钠肽(BNP)、血管紧张素Ⅱ(AngⅡ)及半乳糖凝集素3(Gal-3);心肌进行苏木精-伊红(HE)及Masson染色观察心肌细胞及纤维化,并计算心肌细胞横截面面积(CSA)及胶原体积分数(CVF);此外,分析心肌应变参数和CSA及CVF的相关性。结果 与对照组比较,各模型组,尤其是SHR+复合组的HW/BW、SBP、DBP、血清指标(TC、TG、LDL-C、GLU、GSP、BNP、AngⅡ及Gal-3)和超声心动图参数(LVIDd、LVAWd、LVPWd、IVRT及E/e’)显著升高;斑点追踪超声心动图参数GLS、GLSr、GRS、GRSr、GCS及GCSr的绝对值显著下降;心肌组织HE及Masson染色提示明显心肌细胞肥大及纤维化,并且CSA及CVF显著增加(P<0.05)。相关性分析显示,GLSr、GCS及GCSr与CSA密切相关;GLS、GLSr和GCSr与CVF密切相关(P<0.01)。结论 本研究模拟高血压及糖脂代谢紊乱诱导的HFpEF大鼠模型在病因、临床表现及心肌病理改变上复刻了HFpEF的基本特征,可能是代谢综合征相关HFpEF的可靠动物模型。此外,心肌应变参数与心肌肥厚及纤维化密切相关,可能间接反应心肌细微病变和功能障碍。

Inhibitory effect of antisense basic fibroblast growth factor oligonucleotides on proliferation of cultured aortic smooth muscle cells induced by angiotensin Ⅱ in SHR rats

目的：研究转染反义碱性成纤维细胞生长因子（ｂＦＧＦ）寡核苷酸（ＯＤＮ）对培养的自发性高血压大鼠（ＳＨＲ）主动脉平滑肌细胞（ＳＭＣ）生长的影响．方法：用脂质体介导法将反义ｂＦＧＦＯＤＮ转入ＳＭＣ内，用Ｎｏｒｔｈｅｒｎ杂交检测ｂＦＧＦ基因表达，并测定［３Ｈ］ｔｈｙｍｉｄｉｎｅ掺入和细胞计数．结果：转染反义ｂＦＧＦＯＤＮ（５μｍｏｌ·Ｌ－１）几乎完全抑制血管紧张素Ⅱ（ＡｎｇⅡ，１μｍｏｌ·Ｌ－１）诱导增高的ｂＦＧＦｍＲＮＡ表达和明显抑制ＳＭＣ增殖，在基础状态和ＡｎｇⅡ刺激条件下，［３Ｈ］ｔｈｙｍｉｄｉｎｅ掺入分别被抑制２６５％（Ｐ＜００１）和４２０％（Ｐ＜００１），细胞数分别被抑制１７３％（Ｐ＜００１）和２２２％（Ｐ＜００１）．结论：反义ｂＦＧＦＯＤＮ能有效抑制ＡｎｇⅡ诱导的ｂＦＧＦ基因表达和ＳＭＣ增殖．

Evaluation of Reproductive Characteristics of 21 Highly Inbred Lines of White Leghorns Divergently Selected for or Segregating in Tumor Resistance

Reproduction performance of 21 inbred experimental lines of White Leghorns was evaluated based on samples of reproduction records over a period of eight consecutive years. Two lines (63 and 72) have been extensively used in studies, especially in research seeking for genetic and epigenetic factors underlying resistance to avian tumor virus-induced diseases in chickens. The other 19 lines are recombinant congenic strains (RCS), which were generated by crossing lines 63 and 72 followed by two consecutive backcrosses to the line 63 and then full-sib mating. In theory, each RCS processes 7/8 of progenitor background line 63 genome and a random sample (1/8) of the progenitor donor line 72 genome. All 21 inbred lines share a common major histocompatibility complex haplotype, B*2. The estimated average fertility of the 21 inbred lines ranged from 72.9% (RCS-J) up to 96.8% (RCS-P). Both progenitor lines 63 and 72 were observed with lower average fertility (82.4% and 81.6%, respectively) in comparison with the RCS except the RCS-J, suggesting a substantial polygenic component underlying the fertility phenotype. The average embryo mortality rate ranged from 14.5% (RCS-P) up to 47.0% (RCS-M). The background line 63 fell at about the middle of the range (28.3%) significantly higher than the donor line 72 (15.7%), which was among the group with the lowest embryo mortality. By definition, hatchability of fertile eggs is reversely correlated with embryo mortality. The average hatchability ranged from 26.5% (RCS-M) up to 66.8% (line 72) while the background line 63 remained (46.6%) at about the middle of the range. The variability of the average embryo mortality and hatchability observed among the 21 inbred lines indicated the two correlated traits also follow polygenic models of inheritance. Findings from this study paves the way for further investigation on genetic and environmental influence over reproductive performance of inbred lines of chickens, and particularly in understanding and improving the reproduction fitness of invaluable genetic resources like these inbred lines.

Mechanism and effect of Shijueming (Concha Haliotidis) on serum calcium in spontaneously hypertensive rats

OBJECTIVE: To observe the impact of Shijueming (Concha Haliotidis) on spontaneously hypertensive rats via blood pressure, serum calcium, vascular smooth muscle membrane L-type calcium channel α1 C subunit (CaL-α1C), plasma membrane calcium-ATPase (PMCA) mRNA expression, and the L-type calcium channel in vascular smooth muscle cells. METHODS:Twelve-week-old male rats with spontaneous hypertension were divided into three groups: a Shijueming (Concha Haliotidis) group (group 1), a nifedipine group (group 2), and a distilled water group (group 3). All were given a four-week treatment. Blood pressure and dissociative serum calcium were examined before treatment. Blood pressure was taken every week during treatment. Atomic absorption spectrometry was used to examine dissociative serum calcium. Re-verse transcription-polymerase chain reaction was used to examine the expression of CaL-α1C and PM-CA1 mRNA. The patch clamp technique was used to examine the electrophysiological characteristics of the vascular smooth muscle cell calcium channels. RESULTS: After treatment, blood pressure of the Shijueming (Concha Haliotidis) group lowered but not significantly (P>0.05). Blood pressure of the nifedipine group lowered significantly (P<0.05). Blood pressure of the distilled water group remained high. The concentration of serum calcium in the Shijueming (Concha Haliotidis) and the distilled water groups lowered (P<0.05). Expression of CaL-α1C mRNA in the nifedipine group decreased compared with the distilled water group (P<0.01). There was the decreasing trend in the Shijueming (Concha Haliotidis) group, but it was not statistically significant. Shijueming (Concha Haliotidis) also had effects on the expression of PMCA1 mRNA but with- out statistical significance. However, there was a significant decreasing effect on vascular smooth muscle cell I Ca-L flow. CONCLUSION: This study indicated that Shijueming (Concha Haliotidis) could increase serum calcium and decrease blood pressure. It may work by influencing calcium channels, expression of PMCA1 mRNA, and regulating ion calcium channels and calcium-ATPase.