大鼠睾丸局部热作用对生精细胞Bcl-2及Bax蛋白表达的影响

目的:探讨睾丸局部热作用对大鼠生精细胞凋亡调节蛋白Bcl-2及Bax的影响。方法:雄性Sprague-Dawley大鼠40只,随机分热处理组和对照组,热处理组按热处理后0.5d、1d、3d和6d随机分成4个亚组(n=6),每个亚组相应设立对照组(n=4)。应用免疫组织化学方法检测Bcl-2和Bax在生精细胞的表达。结果:与对照组相比较,热作用后各组Bcl-2阳性细胞表达率及染色阳性细胞Bcl-2含量均显著下降(P<0.01),热作用后各组染色阳性细胞Bax含量均显著增高(P<0.01),除6d组Bax阳性细胞表达率显著下降外(P<0.01),其它各组Bax阳性细胞表达率无差别(P>0.05)。热作用后Bax阳性信号重新分布,从对照组分布在胞浆变成热作用后分布在核周及核。结论:热作用诱导睾丸生精细胞Bcl-2表达下降,Bax表达增高且重新分布。Bcl-2及Bax基因与热诱导生精细胞凋亡发生密切相关。

Effects of Local Testicular Heating on Bcl-2 and Bax Protein Expression in Spermatogenic Cells in Rats

Objectives: To investigate the expression of Bcl-2 and Bax protein in the spermatogenic cells induced by testicular local heating in rats. Methods: Forty adult male SD rats were divided into experimental group and control group randomly. According to days 0.5, 1, 3 and 6 after local testicular heating, each group was divided into 4 subgroups: experimental subgroup (n=6) and control subgroup (n=4). The expression of Bcl- 2 and Bax in the spermatogenic cells was detected on days 0.5, 1, 3 and 6 after heat exposure by immunohisto chemistry. Results: Compared with control groups, the ratios of positive cells and content of Bcl-2 significantly decreased in all experimental subgroups (P<0.01). The content of Bax was increased in all experimental subgroups (P<0.01), the ratio of positive cells had no significant difference (P>0.05) except 6 d group decreased (P<0.01). Redistribution of Bax from a cytoplasmic to perinuclear or nuclear localization could be observed after heating. Conclusions: Expression of Bcl-2 would decrease and Bax would increase with a redistribution in spermatoge- nic cells in rat after heating. The change of Bcl-2 and Bax expression in spermatogenic cells would be correlated with the apoptosis of spermatogenic cell induced by heating.