中文摘要：

目的了解外源性褪黑素（MT）对大鼠视交叉上核中c-fos表达的影响及其可能的调节机制。方法在正常光照（LD=12∶12）和完全黑暗（DD）条件下,在一天中的不同时点给大鼠皮下注射外源性褪黑素,检测视交叉上核（SCN）中c-fos表达的昼夜变化。结果在LD和DD条件下,SCN中c-fos的表达均具有昼夜节律性。给药后LD组昼夜节律的规律性发生了改变,而DD组c-fos表达的节律性仍然保持。与对照组比较,各处理组昼夜节律的中值均显著增大。结论外源性MT能诱导大鼠SCN中c-fos的表达,并改变内源性c-fos的昼夜节律性。

英文摘要：

Objective To investigate the effects of exogenous melatonin （MT） on the c-fos expression in suprachiasmatic nucleus （SCN） of rats. Methods MT was injected to rats subcutaneously at different times of a day under normal light-dark （LD = 12 ： 12） condition and constant darkness （DD）. Circadian changes of the c-fos expression in SCN were examined. Results The expression of c-fos in SCN showed a circadian rhythn raider LD as well as DD. In the LD group, the circadian rhythm changed more evidently than that in the DD group. In both the LD and DD group, the mesors of circadian rhythn increased significantly compared with the control group. Conclusion Exogenous MT could induce the c-fos expression in SCN of rats and clange the circadian rhythn of the c-fos activity.