Kuwahara A, Cooke H J, Carey H V, Mekhjian H, Ellison E C, McGregor B
Department of Physiology, Ohio State University, Columbus 43210.
Dig Dis Sci. 1989 Feb;34(2):206-13. doi: 10.1007/BF01536052.
Nonpathological segments of muscle-stripped left colon from patients undergoing surgery for carcinoma, diverticulitis, or other causes were set up in flux chambers in order to determine the influence of intrinsic neurons on ion transport. In the basal state, both sodium and chloride were actively absorbed, and there was no significant residual ion flux. Electrical field stimulation of the intrinsic mucosal innervation evoked an increase in short-circuit current that was dependent on stimulus frequency and strength. The response was mimicked by scorpion venom, which is known to depolarize neurons, and was nearly abolished by tetrodotoxin, which prevents neurotransmitter release. Atropine reduced, but did not abolish, the response to neural stimulation. Carbachol, aminophylline, and theophylline significantly increased short-circuit current above basal levels. Electrical field stimulation evoked an increase in short-circuit current that could be accounted for by a decrease in net chloride absorption without any significant effect on sodium absorption or residual ion flux. These results suggest that ion transport in the human left colon is regulated by intrinsic submucosal cholinergic neurons as well as other neuronal types, and activation of these nerves could provide the basis for certain diarrheal disorders.
为了确定内在神经元对离子转运的影响，将因癌症、憩室炎或其他原因接受手术的患者的肌肉剥离左结肠的非病理段置于通量室中。在基础状态下，钠和氯均被主动吸收，且没有明显的残余离子通量。对内在黏膜神经支配进行电场刺激可引起短路电流增加，这取决于刺激频率和强度。蝎毒可模拟该反应，已知蝎毒可使神经元去极化，而河豚毒素可几乎消除该反应，河豚毒素可阻止神经递质释放。阿托品可降低但不能消除对神经刺激的反应。卡巴胆碱、氨茶碱和茶碱可使短路电流显著高于基础水平。电场刺激引起短路电流增加，这可归因于净氯吸收减少，而对钠吸收或残余离子通量无任何显著影响。这些结果表明，人类左结肠中的离子转运受内在黏膜下胆碱能神经元以及其他神经元类型的调节，这些神经的激活可为某些腹泻性疾病提供基础。
