慢性束缚应激对大鼠肠粘膜屏障功能的影响

Effects of chronic restraint stress on intestinal barrier function of rats

目的 探讨慢性束缚应激对大鼠肠粘膜屏障功能的影响及其可能存在的损伤和防御机制。方法 将 40只Wistar大鼠按体重随机分为对照组、一周应激组、二周应激组、三周应激组 ,测定各组大鼠的旷场行为 ,血浆D 木糖水平以及小肠肠壁肥大细胞计数 ,血浆皮质醇、乙酰胆碱酯酶 (acetylcholinesterase)、促肾上腺皮质激素释放激素 (CRH )水平 ,血浆和肠粘膜神经降压素 (neurotensin ,NT)含量。结果 旷场实验中 ,应激组大鼠较对照组表现出活动减少的特征 ;血浆D 木糖、皮质醇水平较对照组明显升高 ;肥大细胞计数 ,血浆乙酰胆碱酯酶水平明显降低 ;CRH、NT表现出一个早期升高 ,晚期降低的过程。结论 慢性束缚应激能够导致肠粘膜屏障功能的持续损害 ,其机制可能涉及肥大细胞、胆碱能神经的激活 ,CRH的中枢及外周作用 ;NT可能作为一种保护因子起到防御作用。

Objective To discuss the effect of chronic restraint stress on intestinal barrier function of rats and possible damaging or protective mechanisms in this process.Methods Forty Wistar rats were divided into four groups randomly : normal control,restraint stress groups of different duration(one week,two week,three week).Following varibles were measured:the behavior changes in open field test; the D xylose level in plasma;the numbers of mast cells in small intestine tissues;the levels of cortisol,acetylcholinesterase,CRH,NT in plasma;the content of NT in intestinal mucosa.Results The rats suffered from restraint stress were less active in open field test.The levels of D xylose and cortisol in plasma of stress rats were higher than control group.The numbers of mast cells and the level of acetylcholinesterase in stress rats decreased evidently compared with control.The contents of CRH and NT demonstrated a trend that increased in early stress phase and decreased in late stress phase in comparison with control.Conclusions Chronic restraint stress could cause damage on intestinal barrier function.The mechanism might include the activation of mast cells and cholinergic nerves,the central and peripheral action of CRH. NT maybe a protective factor in this process.