不同时长的束缚应激致雌雄大鼠的抑郁样行为改变

目的探讨不同束缚时长的慢性束缚应激对雌雄SD大鼠抑郁样行为的影响,为慢性束缚应激模型中实验动物性别和实验时长的选择提供依据。方法对SD大鼠(雌雄各半)每天束缚10 h和14 h,连续束缚28 d建立慢性束缚应激模型。采用体重监测、糖水偏爱实验、自主活动实验、新奇事物实验等实验方法,观察不同束缚时长的慢性束缚应激对雌雄SD大鼠所致的抑郁样行为。结果 14 h/28 d CRS组雌雄大鼠的运动时间和中央区活动时间减少、糖水偏爱指数降低、对新奇事物探索潜伏期增多、探索时间和次数减少,这些实验结果与对照组相比均有显著差异。而10 h/28 d CRS组雌雄大鼠与对照组相比以上实验结果仅个别指标有显著性差异。在雌雄鼠比较中,14 h/28 d CRS雄性组的糖水偏爱指数显著减少,对应的雌性大鼠却未显著减少。10 h/28 d CRS雄性组在中央区运动时间比对照组少、对新事物探索潜伏期明显延长、探索时间缩短,而对应雌性大鼠无显著性差异。结论14 h/28 d CRS雌雄鼠在糖水偏爱实验、自主活动实验、新奇事物实验均显著表现出抑郁样行为。而10 h/28 d CRS仅雄性组表现出一定的抑郁样行为的趋势。慢性束缚应激更易致雄性大鼠产生抑郁样行为。

Depressive-like behavior of male and female rats induced by restraint stress with different restraint duration

Objective To investigate the effects of chronic restraint stress on the depressive-like behavior of male and female SD rats with different restraint duration. Methods Sprague-Dawley rats (male and female) were subjected to restraint stress 10 h/14 h daily for 28 days. After that, sucrose preference test, open-field test, novel object test, were performed for all the rats to observe the effects of different restraint duration of chronic restraint stress on the depressive-like behaviors in male and female SD rats. Results For the 14 h/28 d CRS group, including male and female rats, the movement time and central activity time were reduced, sugar consumption index were decreased, novelty exploration time and frequency were reduced, latency were increased, numbers of nose pokes were reduced, and these results were significantly different compared with the control group. There were individual indicators that showed significantly difference for all the above-mentioned behavioral tests of the 10h/28 d CRS group. 14h/28 d CRS male group in syrup consumption index decreased significantly, the corresponding female rats did not significantly reduce. 10h/28 d CRS male group in the central motion time less than that of the control group, and latency was prolonged and exploration time was shortened, while the corresponding female rats had no significant difference. Conclusion 14 h/28 d CRS rats in the sucrose preference test, open-field test, novel object test were exhibited depressive-like behavior, but 10 h/28 d CRS male rats showed a trend of depressive-like behavior. Chronic restraint stress was more likely to lead to depressive-like behavior in male rats.