摘要
目的多种应激方式均能抑制生殖功能,但其对调控机制仍缺少系统的研究。通过观察光照应激状态下SD大鼠睾丸内促性腺激素释放激素(gonadotropin-releasing hormone,GnRH)受体蛋白和mRNA表达变化,为寻找应激状态下生殖系统调节机制提供依据。方法建立SD大鼠光照应激模型,将70只大鼠随机分为14组,其中7组(实验组)24 h持续光照,包括短期光照应激(2、3、4和7d)和长期光照应激(14、21和28d),另7组按正常昼夜节律并作为对照组;分别取实验组和相应对照组的睾丸组织,采用Western blot和RT-PCR分析GnRH受体在各时间段大鼠睾丸组织中的蛋白和mRNA表达变化,并用化学发光法检测血清中睾酮的含量。结果 Western blot结果显示:与对照组比较,持续光照2、3、4和7 d后,实验组大鼠睾丸GnRH受体表达无明显变化;持续光照14d和21d后,实验组大鼠睾丸GnRH受体的表达分别升高了27.8%±11.2%和40.6%±24.8%,差异具有统计学意义(P<0.05);持续光照28 d后,实验组大鼠睾丸GnRH受体的表达升高了26.1%±33.6%,但差异无统计学意义(P>0.05)。RT-PCR结果显示:GnRH受体的mRNA表达和其蛋白表达呈现相同的趋势,但差异无统计学意义(P>0.05)。随着光照时间的延长,睾酮分泌量与对照组相比持续上升,差异有统计学意义(P<0.05)。结论 GnRHR随着光照应激时间的延长,在大鼠睾丸中蛋白表达量发生改变。提示在光照应激中,GnRH受体对生殖功能具有潜在的生理调节功能。
Objective Many kinds of stress can suppress reproduction,but systematic researches are yet absent on its regulatory mechanism.The aim of this study was to observe the changes in the expression of the（gonadotropin-releasing hormone） GnRH receptor in the testis of SD rats under constant light stress.Methods We established short-term（2,3,4,and 7 days） and long-term（14,21 and 28 days） light-stress models in 70 SD rats,and exposed them to round-the-clock light（the experimental group） and normal daylight（the control group）.Then we collected the testis tissues of the rats for the analysis of the changes in the GnRHR expression by Western blot and RT-PCR and determination of the testosterone level in the serum using a chemoluminescent technique.Results Compared with the control group,the GnRHR expression showed no significant changes in the experimental group at 2,3,4 and 7 days,but was increased（27.8 ± 11.2） %（P0.05）,（40.6 ± 24.8） %（P0.05） and（26.1 ± 33.6） %（P0.05） at 14,21 and 28 days,respectively.The mRNA expression of GnRHR exhibited a similar increase to its protein expression,but with no statistically significant difference.The level of testosterone was significantly elevated with the increased time of light stress in the experimental group as compared with the controls（P0.05）.Conclusion The expression of the GnRH receptor changed with the increased time of light stress,which suggests that GnRHR could regulate reproductive function under light stress.
出处
《医学研究生学报》
CAS
2011年第2期122-126,共5页
Journal of Medical Postgraduates
基金
国家自然科学基金(30770801)
全军"十一五"医药卫生科研基金(06H011)
关键词
光照
应激
睾丸
促性腺激素释放激素
Constant light
Stress
Testis
Gonadotropin-releasing hormone
