Ando K, Takahashi K, Ono A, Shimosawa T, Ogata E, Fujita T
Fourth Department of Internal Medicine, University of Tokyo School of Medicine, Japan.
Biochem Biophys Res Commun. 1991 May 31;177(1):407-13. doi: 10.1016/0006-291x(91)91998-r.
The decreased extracellular Na concentration (25mM) attenuated vasodilator effect of acetylcholine (ACh) in norepinephrine-treated aortic ring. This attenuation was greater in the low Na medium substituted by Li, which can exchange intracellular H through Na-H antiport, as compared with that substituted by choline, which cannot. 10 microM amiloride canceled the difference between the two low Na mediums. Thus the inhibition of Na-H antiport may counteract the suppressive effect of decreased intracellular Na on ACh vasodilation, suggesting a possible role of Na-H antiport in a release of vasoactive substance(s) from endothelial cells.
细胞外钠离子浓度降低（25mM）减弱了去甲肾上腺素处理的主动脉环中乙酰胆碱（ACh）的血管舒张作用。与不能透过细胞膜的胆碱替代的低钠培养基相比，在锂替代的低钠培养基中这种减弱作用更明显，锂可通过钠-氢反向转运体交换细胞内的氢离子。10微摩尔的氨氯地平消除了两种低钠培养基之间的差异。因此，抑制钠-氢反向转运体可能会抵消细胞内钠离子减少对乙酰胆碱血管舒张作用的抑制效应，这表明钠-氢反向转运体在内皮细胞释放血管活性物质过程中可能发挥作用。
