睾酮对慢性心力衰竭雄性大鼠心肌纤维化的影响

Effect of testosterone on myocardial fibrosis of male rats with chronic heart failure

目的探讨睾酮对慢性心力衰竭雄性大鼠心脏纤维化的影响。方法将53只雄性SD大鼠分为正常对照组(A组)、睾丸切除加心力衰竭组(B组)、睾丸切除加心力衰竭加睾酮(T)替代治疗组(C组)。应用放射免疫法检测大鼠血浆T和肿瘤坏死因子-α(TNF-α)水平,免疫组化检测心肌组织转化生长因子-β1(TGF-β1)表达水平,VG染色观察大鼠心肌间质胶原纤维的变化。结果与B组比较,C组TNF-α水平明显降低[C组vs.B组:(0.86±0.27)ng/mL vs(1.28±0.26)ng/mL,P<0.01],TGF-β1水平明显降低[C组vs.B组:(3.32±1.61)%vs(6.49±2.82)%,P<0.01],胶原容积分数(CVF)减少[C组vs.B组:(2.13±0.72)%vs(2.84±0.79)%,P<0.05]。结论睾酮能抑制心力衰竭雄性大鼠心肌纤维化,从而保护心功能,其作用的一个重要机制可能为睾酮拮抗TGF-β1的产生。

Objective To investigate the effect of testosterone on myocardial fibrosis of male rats with chronic heart failure（HF）.Methods Fifty-three male SD rats were divided into 3 groups： control group（group A）,orchiectomy＋HF（group B）,and orchiectomy＋HF＋testosterone（T）（group C）.The levels of testosterone and cytokine（TNF-α） were measured by radioimmunoassay, TGF-β1 was detected by immunohistochemical method,and interstitial collagen of myocardial cell was observed by V-G staining.Results Compared with group B,plasma TNF-α level was dramatically decreased in group C（group C 0.86±0.27 ng/mL and group B 1.28±0.26 ng/mL,P0.01）,plasma TGFβ1 level was significantly reduced（group C 3.32±1.61% and group B 6.49±2.82%,P0.01）,and the collagen volume fraction dropped as well（group C 2.13±0.72% and group B 2.84±0.79%,P0.05）.Conclusion In male rats with HF,testosterone exerts a suppressive effect on myocardial fibrosis mostly due to its inhibition to TGF-β1.