Cooke H J
Department of Neuroscience, Ohio State University, 333 W. 10th Avenue, Columbus, OH 43210, USA.
Ann N Y Acad Sci. 2000;915:77-80. doi: 10.1111/j.1749-6632.2000.tb05225.x.
The intestinal crypt cell secretes chloride into the lumen, resulting in accumulation of fluid that normally thins out mucus or, at higher secretory rates, flushes out the contents. The regulation of chloride secretion occurs by neural reflex pathways within the enteric nervous system. Mechanical stimulation releases 5-hydroxytryptamine (5-HT) from enterochromaffin cells with subsequent activation of intrinsic primary afferents that carry electrical signals to submucosal ganglia. After processing, interneurons activate cholinergic and vasoactive intestinal peptide (VIP) secretomotor neurons. Acetylcholine and VIP bind to epithelial receptors and stimulate sodium chloride and fluid secretion. Reflex-evoked secretory rates can be modulated by a variety of mediators at the level of the enterochromaffin cells, neurons within the reflex pathway, or epithelial cells. Understanding the complex regulatory mechanisms for chloride secretion is likely to provide mechanistic insights into constipation and diarrhea.
肠隐窝细胞向肠腔分泌氯离子，导致液体积聚，这种液体通常会稀释黏液，或者在分泌速率较高时将肠内容物冲洗出去。氯离子分泌的调节通过肠神经系统内的神经反射途径进行。机械刺激会促使肠嗜铬细胞释放5-羟色胺（5-HT），随后激活内在初级传入神经，这些神经将电信号传递至黏膜下神经节。经过处理后，中间神经元激活胆碱能和血管活性肠肽（VIP）分泌运动神经元。乙酰胆碱和VIP与上皮受体结合，刺激氯化钠和液体分泌。反射诱发的分泌速率可在肠嗜铬细胞、反射途径内的神经元或上皮细胞水平受到多种介质的调节。了解氯离子分泌的复杂调节机制可能为便秘和腹泻提供机制上的见解。
