Changes in androgen receptor protein and mRNA expressions in intracardiac ganglia of orchidectomized rats / 中国组织工程研究

ABSTRACT

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.OBJECFIVETo 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.MATERIALSThis 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 groups①Control 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.