Seligman J, Kosower N S, Shalgi R
Department of Human Genetics, Sackler School of Medicine, Tel Aviv University, Israel.
Mol Reprod Dev. 1997 Jul;47(3):295-301. doi: 10.1002/(SICI)1098-2795(199707)47:3<295::AID-MRD8>3.0.CO;2-G.
Mammalian spermatozoa gain their fertilizing ability as they mature in the epididymis, a process which is accompanied by oxidation of sperm protein thiols. Since sperm maturation is dependent upon normal androgenic support to the epididymis, the present work was designed to study the effects of castration on thiol status. Spermatozoa and epididymal fluid were isolated from the epididymides of male rats 5 days after castration or after 11 daily injections of the antiandrogen, cyproterone acetate. Spermatozoa and epididymal fluid were labeled with the fluorescent thiol labeling agent monobromobimane. Intact spermatozoa were evaluated by fluorescence microscopy, protein thiols were analyzed by electrophoresis, and fertilizing ability was examined after insemination of sperm suspension into the uterine horns of immature superovulated female rats. We found that both treatments resulted in an increase in cauda sperm thiols as shown by increased fluorescence in the intact spermatozoa. Protamines and nonbasic proteins were found to have increased levels of reactive thiols. The protein profiles of epididymal fluid from castrated rats were different from those of the controls, and the fluorescence patterns corresponded to the protein profiles. Our results indicate that testosterone withdrawal leads to inhibition of sperm thiol oxidation.
哺乳动物精子在附睾中成熟时获得受精能力，这一过程伴随着精子蛋白硫醇的氧化。由于精子成熟依赖于附睾正常的雄激素支持，因此本研究旨在探讨去势对硫醇状态的影响。在去势5天后或每日注射抗雄激素药物醋酸环丙孕酮11天后，从雄性大鼠的附睾中分离出精子和附睾液。精子和附睾液用荧光硫醇标记剂单溴代双马来酰亚胺进行标记。通过荧光显微镜评估完整精子，通过电泳分析蛋白质硫醇，并将精子悬液注入未成熟超排卵雌性大鼠的子宫角后检查受精能力。我们发现，两种处理均导致附睾尾部精子硫醇增加，完整精子中的荧光增强表明了这一点。发现鱼精蛋白和非碱性蛋白的反应性硫醇水平增加。去势大鼠附睾液的蛋白质谱与对照组不同，荧光模式与蛋白质谱相对应。我们的结果表明，睾酮缺乏会导致精子硫醇氧化受到抑制。
