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。
The O subfamily of forkhead box(FoxO) proteins is the downstream effector of the insulin-like growth factor-1/phosphoinositide 3-kinase/protein kinase B(IGF-1/PI3K/PKB) signal pathway.The objective of the present study was to examine the expressions of three members of FoxO proteins,FoxO1,FoxO3a,and FoxO4 in the duodenum of Sprague-Dawley rats at different ages.The result demonstrated that the expression of FoxO4 in rat duodenum showed an age-dependent manner.At Day 21,there were no detectable localization and expression of FoxO4 in the duodenum,while,at Months 2 and 6,localization and expression of FoxO4 were distinct.In addition,FoxO4 staining was primarily concentrated in the cell nuclei of the lamina propria around the intestinal gland of the duodenum in 2-month-old rats,but was not detectable in the same area in 6-month-old rats.Our results showed also that although FoxO3a existed in the cytoplasm of the lamina propria at a low level at the 2-and 6-month marks,it was still not detectable at Day 21.Besides,FoxO1 was not detectable in all parts and stages.Taken together,our findings suggested that the cell-specific and age-dependent expressional patterns of FoxO4 and FoxO3a proteins in the duodenum play some roles in the development and growth performance of the rat duodenum.
Pan HUANG Zhen-qi ZHOU Rui-hua HUANG Bo ZHOU Quan-wei WEI Fang-xiong SHI
Objective: The present study is designed to investigate the cellular expressions and immunolocalizations of three different nitric oxide synthase (NOS) isoforms and the related nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway in the ovaries of neonatal and immature rats.Methods: The ovaries were obtained from ICR (Institute for Cancer Research) female Sprague-Dawley rats at postnatal days 1,5,7,10,and 19.Then we carried out the histologic examination,immunohistochemistry,measurement of NOS activity,and modifications within the NO/cGMP pathway.Results: During postnatal days 1,5,7,10,and 19,all three isoforms of NOS were mainly localized to the oocytes and expressed as a gradual increase in granulosa cells and theca cells within the growing follicle.The ovarian total NOS activities and NO levels were increased at postnatal days 7 and 10 compared with other days.Conclusions: Our findings suggest that the locally produced NO and the NO/NOS signaling systems are involved in the follicular development to puberty.
Wei ZHANG Quan-wei WEI Zheng-chao WANG Wei DING Wei WANG Fang-xiong SHI
