中文摘要：

目的探讨神经肽Y（NPY）和5-羟色胺（5-HT）对腹泻型肠易激综合征（D-IBS）发病机制的影响,为从脑肠轴方面分析研究D-IBS的发生机制提供理论依据。方法采用母乳分离＋醋酸刺激＋四肢束缚制作D-IBS大鼠模型,通过免疫组化法检测大鼠结肠组织中5-HT的蛋白表达水平,采用实时荧光定量RT-PCR检测大鼠下丘脑和结肠组织中NPY mRNA的表达。结果与正常组相比,NPY mRNA表达在肠易激综合征模型大鼠结肠和下丘脑组织均降低（P〈0.05）。5-HT蛋白表达在模型大鼠结肠中升高（P〈0.05）。结论脑肠肽NPY和5-HT可能参与D-IBS脑肠轴异常机制的调节。

英文摘要：

Aim To investigate expression of neu-ropeptide Y（NPY） and 5-hydroxy tryptamine （5-HT） in diarrhea-predominant irritable bowel syndrome （D- IBS） and provide theoretical basis for mechanism of D- IBS from the aspect of brain-gut axis. Method A rat model of D-IBS was established with the use of separation of breast milk ＋ stimulation of acetic acid ＋ con- straint of the four limbs. Expression of 5-HT protein was detected in colon of rat with immunohistochemistry and expression of NPY mRNA was detected in colon and hypothalamus of rat with real-time fluorescence quantitative reverse transcription polymerase chain reaction （ RT-PCR ）. Result Compared with normal group, expression of NPY mRNA were significantly de- creased in colon and hypothalamus of D-IBS model group （P 〈 0.05）. In addition, 5-HT protein expression was markedly increased in colon of D-IBS model group （P 〈 0. 05 ）. Conclusion NPY and 5-HT may be involved in regulatory mechanism of D-IBS.