Diener M, Vujicic Z, Scharrer E
Institute for Veterinary Physiology, University of Zürich, Switzerland.
Acta Physiol Scand. 1996 May;157(1):33-40. doi: 10.1046/j.1365-201X.1996.470184000.x.
The short-chain fatty acids acetate, propionate and butyrate induced a concentration-dependent increase of short-circuit current (Isc) in the rat distal small intestine in vitro. They were ineffective in the proximal small intestine. The increase of lsc in the distal small intestine was dependent on the presence of Cl- and HCO3- ions. It was blocked by the inhibitor of the Na(+)-K(+)-Cl(-) -cotransporter, bumetanide, and by the Cl- channel blocker, 5-nitro-2-(3-phenylpropylamino)-benzoate, indicating that short-chain fatty acids evoke an anion secretion. The secretion induced by propionate was blocked by the neurotoxin, tetrodotoxin, and inhibited by the muscarinic antagonists, atropine. In contrast, indomethacin, a cyclooxygenase inhibitor, or nordihydroguaiaretic acid, a lipoxygenase inhibitor, were ineffective. These results indicate that short-chain fatty acids stimulate chemosensitive neurones in the rat small intestine in a region-specific manner, which induce anion secretion by the release of mainly acetylcholine.
短链脂肪酸乙酸盐、丙酸盐和丁酸盐在体外可使大鼠远端小肠的短路电流（Isc）呈浓度依赖性增加。它们在近端小肠中无此作用。远端小肠中Isc的增加依赖于Cl-和HCO3-离子的存在。它被Na(+)-K(+)-Cl(-)协同转运体抑制剂布美他尼以及Cl-通道阻滞剂5-硝基-2-(3-苯丙基氨基)-苯甲酸所阻断，这表明短链脂肪酸可引起阴离子分泌。丙酸盐诱导的分泌被神经毒素河豚毒素阻断，并被毒蕈碱拮抗剂阿托品抑制。相比之下，环氧化酶抑制剂吲哚美辛或脂氧合酶抑制剂去甲二氢愈创木酸则无效。这些结果表明，短链脂肪酸以区域特异性方式刺激大鼠小肠中的化学敏感神经元，这些神经元主要通过释放乙酰胆碱来诱导阴离子分泌。
