摘要
Objective： To investigate male reproductive parameters via changes of potential testicular protein markers in restraint-stress rats. Methods： Male Sprague-Dawley rats were divided into two groups （non-immobilized control and restraint-immobilized/stress groups, n=8 each group）. The stress animals were immobilized （12 h/d） by a restraint cage for 7 consecutive days. All reproductive parameters, morphology and histology were observed and compared between groups. In addition, the expression of steroidogenic acute regulatory （STAR） and phosphotyrosine proteins （previously localized in Sertoli and late spermatid cells） in testicular lysate was assayed by immuno-Western blotting. Results： Testosterone level, sperm concentration and sperm head normality of stress rats were significantly decreased while the corticosterone level was increased as compared with the control （P〈0.05）. Histologically, stress rats showed low sperm mass in epididymal lumen and some atrophy of seminiferous tubules. Although the expression of testicular STAR protein was not significantly different between groups, changed patterns of the 131, 95, and 75 kDa testicular phosphorylated proteins were observed in the stress group compared with the control group. The intensity of a tes- ticular 95-kDa phosphorylated protein was significantly decreased in stress rats. Conclusions： This study has demonstrated the alteration of testicular phosphorylated protein patterns, associated with adverse male reproductive parameters in stress rats. It could be an explanation of some infertility in stress males.
目的:寻找雄性大鼠应激模型中潜在的睾丸蛋白标记物,探索评估男性生殖能力新的参数。创新点:压力可以影响男性生育能力,但其具体机制尚未明了。睾丸组织中酪氨酸磷酸化蛋白在精子形成过程中扮演着重要的角色。本研究首次利用动物模型说明了压力对睾丸组织中酪氨酸磷酸化蛋白表达的影响,进而探索评估男性生殖能力新的参数。方法:雄性SD大鼠被随机分为对照组和束缚应激的实验组。实验组大鼠每天禁足12小时,持续7天。观察比较两组类固醇激素、精子密度、生殖系统形态学和组织学的差别,同时利用免疫印迹方法比较两组睾丸组织裂解产物中急性类固醇调节蛋白和酪氨酸的表达差别(早期在支持细胞中表达,后期在精子细胞中表达)。结果:实验组大鼠的睾酮水平和精子密度较对照组均显著降低,而精子畸形率和皮质酮显著升高。组织学比较发现实验组大鼠精子团数量减少并且出现输精管萎缩。两组大鼠睾丸组织中酪氨酸磷酸化蛋白的表达具有显著差异,实验组95 k Da的磷酸化蛋白表达量显著降低,但两组急性类固醇调节蛋白的表达没有显著差异。结论:本研究证明束缚应激可使大鼠睾丸组织磷酸化蛋白表达降低,并相应伴随着生殖能力参数的降低。这也许可以从一个方面解释压力对男性不育的影响。
基金
Project supported by the Postgraduate Study Support Grant and Invitation Research Grant(IN59134),Faculty of Medicine
Khon Kaen University,Khon Kaen,Thailand
