精索静脉曲张大鼠睾丸细胞线粒体钙、Bcl-2/Bax蛋白表达和细胞凋亡的研究

Study on the mitochondria Ca 2+, expression of Bcl-2 and Bax and germ cell apoptosis in testes of rats with varicocele

目的:研究精索静脉曲张(VC)大鼠睾丸细胞线粒体钙、Bcl-2/Bax蛋白表达与细胞凋亡及其机制。方法:选取35只成年健康雄性Wistar大鼠,随机分为VC组(VG,n=20)和假手术组(SOG,n=15)。术后10周,取双侧睾丸,采用火焰原子吸收法测定线粒体钙、采用原位缺口末端标记法(TUNEL)检测生殖细胞凋亡,免疫组化SABC法检测Bcl-2/Bax蛋白表达。结果:VC组大鼠双侧睾丸生殖细胞线粒体钙的含量明显低于SOG组,生殖细胞凋亡显著增多,Bcl-2表达显著降低,Bax表达显著升高,但双侧睾丸生殖细胞凋亡率差异无显著。结论:VC时,大鼠睾丸生殖细胞凋亡明显增加,提示VC时所致的男性不育可能是在某种凋亡诱发因素(高温、毒素返流、氧自由基等)作用下,线粒体钙、Bcl-2/Bax蛋白表达的变化直接对生殖细胞产生影响,导致男性不育。

AIM： The cytoplasm Ca^2＋ , expression of Bcl- 2 and Bax and germ cell apoptosis of testes in adult male rats with varicocele were observed to investigate the relationship between apoptosis and infertility. METHODS： Thirty- five healthy male Wistar rats were divided into two groups randomly： varicoeele group （VG, n = 20） and sham operation group （SOG, n = 15）. Bilateral testes were removed after ten weeks. One part of it was homogenized, the other part was performed for tissue sectioning. The atomic absorption method was used to detect the cytoplasm Ca^2 ＋ . The germ cell apoptosis was detected by the TdT - mediated duTP- biotin nick end labeling （TUNEL） technique. The expression of Bcl - 2/Bax was detected by immunohistochemical method. RESULTS： The cytoplasm Ca^2＋ in testes of rats with varicocele was decreased obviously. The apoptosis indexes of germ cells and Bax expression in VG were significantly increased as compared with those in the SOG, while Bcl - 2 expression was obviously decreased. CONCLUSION： The results showed that apoptosis was increased in testes of VG rats, suggesting that male infertility with varicocele may be caused by some apoptosis agents such as high temperature, testes toxin and oxygen free radical. The cytoplasm Ca^2＋ and change of expression of Bcl - 2/Bax may contribute to germ cell apoptosis and cause male infertility.