论文部分内容阅读
目的:探讨急性热应激对性成熟雄性小鼠睾丸、附睾、输精管中热休克蛋白70(heat shock protein 70,HSP70)表达的影响。方法:将32只8周龄雄性小白鼠随机均分为4组,饲养7d后,进行热应激处理,温度控制在(39±0.5)℃,时间分别为0.5、1和3h。应激后立即采血,分离血清测定谷草转氨酶(GOT)含量。一侧附睾制备精子悬液,用于计算精子密度和顶体畸形率;另一侧附睾、睾丸、输精管用于免疫组化研究。结果:应激后,小鼠体重、睾丸系数、顶体畸形率变化不显著(P>0.05),附睾系数和精子密度有不同程度的下降,GOT含量急剧升高(P<0.01)。随着应激时间的延长,小鼠精子密度呈递减趋势,顶体畸形率呈上升趋势。应激时间最短的0.5h组小鼠体重、睾丸系数、附睾系数的降幅反而最大。免疫组化法观察发现,HSP70在性成熟小鼠睾丸、附睾、输精管中均有表达。正常状态下,HSP70在睾丸组织间质细胞中少量表达,应激后分布于间质细胞核,此外在精母细胞核与精子细胞核中也有大量分布;附睾中HSP70主要分布于主细胞质,基细胞和亮细胞中没有表达,应激后附睾体的纤毛细胞中也发现大量棕色颗粒;输精管中HSP70主要定位在基细胞质,主细胞中不表达。随着应激时间的延长,HSP70在睾丸、附睾中的表达量明显升高,而在输精管中的增幅不明显。结论:急性热应激对性成熟雄性小鼠的生殖系统造成了损伤;HSP70在睾丸、附睾、输精管中的表达与定位具有区域特异性和细胞特异性,提示其可能参与精子的发生与成熟;HSP70在应激状态下表达量大幅上升的作用可能在于保护细胞免受高热损伤。
Objective: To investigate the effects of acute heat stress on the expression of heat shock protein 70 (HSP70) in testis, epididymis and vas deferens of sexual matured male mice. Methods: 32 8-week-old male mice were randomly divided into 4 groups. After 7 days of rearing, they were treated with heat stress and the temperature was controlled at (39 ± 0.5) ℃ for 0.5, 1 and 3 h respectively. Blood samples were collected immediately after stress and the serum was assayed for the content of aspartate aminotransferase (GOT). One side of the epididymis sperm suspension preparation for the calculation of sperm density and acrosome deformity rate; the other side of the epididymis, testis, vas deferens for immunohistochemistry. Results: After stress, the body weight, testicular coefficient and acrosomal deformity did not change significantly (P> 0.05). The epididymal coefficient and sperm density decreased to some extent and the content of GOT increased sharply (P <0.01). With the prolongation of stress time, the sperm density of mice showed a decreasing trend, and the acrosome deformity rate showed an upward trend. The body weight, testis coefficient and epididymal coefficient of 0.5h group with the shortest stress time had the largest decline. Immunohistochemistry showed that HSP70 was expressed in the testes, epididymis and vas deferens in mature mice. Under normal conditions, HSP70 is expressed in a small amount in testicular stromal cells and distributed in interstitial nucleus after stress. In addition, HSP70 is also distributed in nucleus and sperm nucleus of spermatocytes. HSP70 in epididymis is mainly distributed in the main cytoplasm, Cells were not expressed, a large number of brown particles were also found in the ciliated cells of the epididymis after stress. The vas deferens HSP70 mainly located in the basal cytoplasm, but not in the main cells. With the prolongation of stress time, the expression of HSP70 in testis and epididymis increased obviously, but not in vas deferens. CONCLUSION: Acute thermal stress causes damage to the reproductive system in sexual matured male mice. The expression and localization of HSP70 in testis, epididymis and vas deferens are region specific and cell specific, suggesting that HSP70 may be involved in the development and maturation of sperm. The role of HSP70 in the expression of a significant increase in stress may be to protect cells from high heat damage.