直肠扩张刺激引起IBS大鼠痛行为学以及骶髓DCN中神经元和胶质细胞的变化

The changes of ethology and the neuron and glia of dorsal commissural nucleus induced by distented the colon of rats with IBS

目的采用行为学和免疫荧光化学的方法,观察直肠扩张刺激对IBS大鼠痛行为学以及大鼠骶髓后连合核(dorsal com-missural nucleus,DCN)中神经元和胶质细胞的影响,为探讨IBS发生机制提供理论依据。方法动物分组:正常大鼠6只为空白对照组;感染旋毛虫的IBS大鼠42只,随机均分为7组:直肠放置气囊对照组、0.6 ml组、0.8 ml组、1.0 ml组、1.2 ml组、1.4 ml组和1.5 ml组。应用疼痛行为学的观察方法,观察1 h各组动物的行为学改变,并采用免疫荧光化学的方法,观察大鼠DCN中神经元被激活的标志c-fos及胶质细胞的胶质原纤维酸性蛋白(glial fibrillary acidic protien,GFAP)和小胶质细胞特异性补体OX42的表达情况,空白对照组是在疼痛高峰点(1.2 ml)处死取材。结果正常大鼠痛行为学积分在1.2 ml组最为高,实验组IBS大鼠在0.8 ml组的痛行为学最为明显,基本上达到痛行为学反应的高峰,可见IBS大鼠的痛阈值低于正常大鼠。对照组(1.2 ml)中正常大鼠DCN中的c-fos、GFAP表达水平只相当于IBS中的0.8 ml组的表达水平,低于1.0 ml、1.2 ml、1.4 ml组;OX42的活化程度也较低只相当于IBS中的1.2 ml组,并且明显低于1.4 ml、1.5 ml组。结论直肠扩张刺激明显引起IBS鼠痛行为的变化不但与骶髓中神经元活动存在密切关系,而且与神经胶质的活化可能也存在密切联系。

Objective To detect the effects of ethology, the neuron and glia of dorsal commissural nucleus （DCN） in rats with irritable bowel syndrome （IBS） induced by distented the colon, and provide theory evidence for the pathogeny of IBS. Methods Group A（the normal rats） was NS group. The forty two rats which was infected the trichina worm through their gastrointestinal tract were divided into seven groups randomly. Rat in Group B was set an air bladder which was empty and not perfused water. Water of 0. 6 ml,0. 8 ml, 1.0 ml,1.2 ml,1.4 ml and 1.5 ml was perfused respectively into the air bladders which were set in the colon of rats in group C,D,E,F, G and H. Then the changes of ethology of the rats were recorded in interval of an hour. By using immunofluorescece histochmistry to respectively detect the expressions of c-fos,glial fibrillary acidic protein（GFAP） and OX42,which were markers for neuron,astrocyte and microglia in DCN. Results On ethology, the threshold of pain of rats with IBS was obvious under the normal control group. The results of immunofluorescece histochmistry showed that the expressions of c-fos and GFAP in group A approximate group D and are under group E, F, G, H ; the ex- pressions of OX42 of group A approximate group F,and are under group G,H . Conclusion The changes of ethology rats with IBS connect with hyperalgesia. The hyperalgesia in IBS rats probably is related with the neuron and glia in DCN.