雄性大鼠去睾丸后心内神经节雄激素受体蛋白及其mRNA表达的变化

摘要

BACKGROUND:Most foreign and domestic studies on the effect of androgen receptor(AR) on cardiovascular system are limited to myocardium.However,cardiac nervous system plays an important role in the cardiac functional regulation.OBJECFIVE:To observe the AR protein and mRNA expressions in intracardiac ganglia of male orchidectomized rats,to investigate whether androgen affects the expressions,and to make a comparison with normal rats and testosterone-substituted rats after orchiectomy.DESIGN:A randomized controlled experiment.SETTING:Department of Anatomy,Medical College,Wuhan University of Science and Technology;Department of Anatomy,Tongji Medical College,Huazhong University of Science and Technology.MATERIALS:This study was carried out in the Department of Anatomy,Medical College,Wuhan University of Science and Technology between January and May 2003.Sixty healthy adult male Wistar rats,with body mass of 150 to 250g,were provided by the Animal Experimental Center,Tongji Medical College,Huazhong University of Science and Technology.METHODS:Sixty rats were randomized into 3 groups:①Control group,in which,testicles of rats were untouched.②Orchiectomy group,in which,bilateral testicles of rats were dissected.③Testosterone group,in which,the orchidectomized rats were injected with testosterone,0.2 mg once,once every 3 days,3 weeks totally.AR protein and its mRNA expressions in intracardiac ganglia of male orchidectomized rats were detected by immunohistochemical method and in situ hybridization method.MAIN OUTCOME MEASURES:The positive rate of AR-positive cells in intracardiac ganglia (the number of positive cells/the number of total cells×100%)and its mean absorbance.RESULTS:All the 60 rats were involved in the final analysis.AR-positive nerve cells were found in all the intracardiac ganglia of atrial posterior wall in the 3 groups;The positive rate of AR protein and mRNA positive nerve cells in intracardiac ganglia and its mean absorbance were significantly lower in the orchiectomy group than in the control group and in the testosterone group (P＜0.05).But no obvious differences in the positive rate and mean absorbance existed between testosterone group and control group(P＞0.05).CONCLUSION:AR exists in the intracardiac ganglia of atrial posterior wall,and it is regulated by androgen.%背景:国内外对雄激素受体在心血管方面的研究多局限于心肌,忽视了心内神经系统,而心内神经系统在心脏的功能调节中起十分重要的作用.目的:观察雄激素受体蛋白及其mRNA在睾丸切除后大鼠心内神经节的表达及其是否受雄激素的影响,并与正常及睾丸切除后睾酮替代大鼠比较.设计:随机对照实验.单位:武汉科技大学医学院解剖学教研室,华中科技大学同济医学院解剖学系.材料:实验于2003-01/05在武汉科技大学医学院解剖学教研室完成.选用健康成年雄性Wistar大鼠60只,体质量150～250 g,由华中科技大学同济医学院动物实验中心提供.方法:将60只大鼠随机分为3组:①对照组:不切除睾丸.②睾丸切除组:切除大鼠双侧睾丸.③睾酮替代组:大鼠睾丸切除后注射睾酮0.2 mg/次,1次/3 d,持续3周.采用免疫组织化学法和原位杂交法检测大鼠心内神经节雄激素受体阳性细胞及其mRNA的表达.主要观察指标:各组大鼠心内神经节雄激素受体阳性细胞的阳性率(阳性细胞数/总细胞数×100%)及其平均吸光度值.结果:大鼠60只全部进入结果分析.3组大鼠心内神经节均存在雄激素受体阳性神经细胞;与对照组相比,睾丸切除组大鼠心内神经节雄激素受体及其mRNA表达的阳性神经细胞阳性率和平均吸光度值均明显低于对照组和睾酮替代组(P＜0.05),但睾酮替代组与对照组比较,差异不明显(P＞0.05).结论:心房后壁心内神经节存在雄激素受体,并且受雄激素调节.