杏仁核注射5-HT对慢性应激抑郁大鼠胃运动的影响

The effect of 5-HT microinjection into amygdaloid nucleus on the gastric mobility in CUMS treated-rats

运用慢性不可预见性温和应激建立抑郁模型,通过体重变化率、糖水偏好、敞箱等实验方法观察大鼠行为表现及胃运动,探讨慢性应激性抑郁大鼠胃活动的变化及杏仁核注射5-HT对慢性不可预见性应激引起的胃活动变化的影响.结果显示,慢性不可预见性应激引起大鼠体重呈负增长,糖水偏好率、敞箱实验评分显著降低;应激大鼠平均胃内压及胃收缩幅度也显著降低;杏仁核注射5-HT能明显改变应激性抑郁导致的胃活动减弱,5-HT1A受体阻断剂能明显影响5-HT的作用;切断双侧膈下迷走神经,杏仁核注射5-HT增强胃运动的效应被消除.以上结果说明,慢性不可预见性应激性抑郁可导致胃运动减弱,杏仁核注射5-HT可加强抑郁状态下胃运动,而5-HT的这种效应部分是由1A型受体介导,经迷走神经传出.

In order to investigate the changes of gastric mobility in chronic unpredicted mild stress （CUMS）, and the effect of 5-HT microinjection into amygdaloid nucleus on the changes of gastric mobility induced by CUMS , the depression model of rats established by CUMS was used. By observing the behavior of open field-test, sucrose preference-test, forced swimming- test and the changes in body weight , and then examining the effects of intra-amygdaloid injection of 5-HT on the gastric mobility, some information has been obtained. The results show that the percentage of sucrose preference, the scores of locomotion , rearing, grooming in CUMS group extremely reduced and the body weight gain was negative; the intragastric pressure and gastric motility markedly decreased;intraamygdaloid injection of 5-HT could markedly improve the gastric mobility reduced by CUMS, which could be affected by the 5-HT1A receptor antagonist spiperone;the improvement of the gastric mobility induced by intra-amygdaloid injection of 5-HT was eliminated when vagotomy was severed. These results suggest that CUMS can actually reduce the gastric mobility. Intra-amygdaloid injection of 5- HT can improve the gastric mobility of CUMS treated-rats, which can be partly attributed to mediation of receptor antagonist spiperone and transmittance by vagus.