乙酰胆碱和高钾引发肾上腺儿茶酚胺释放的不同机制

Contrasting mechanisms of adrenal catecholamine release by acetylcholine and high potassium.

作者信息

Baugh L E, Borowitz J L, Leslie S W

出版信息

Res Commun Chem Pathol Pharmacol. 1976 Jul;14(3):407-20.

Abstract

Continuous twenty minute exposure of isolated perfused bovine adrenal glands to high potassium concentrations produced shorter durations of catecholamine release than twenty minute continuous stimulation with acetylcholine. Catecholamine release during continuous exposure to potassium decreased linearly on a semilog plot, whereas acetylcholine caused a biphasic release of catecholamine. Glands previously treated with high potassium responded poorly to acetylcholine; however, glands previously treated with acetylcholine showed a maximum response to high potassium concentrations. Full recovery of the response to acetylcholine after high potassium treatment occurred in twenty minutes. High potassium concentrations appear to evoke secretion of "readily releasable" material only, whereas acetylcholine has access to a larger catecholamine store in the adrenal.

摘要

将分离灌注的牛肾上腺连续暴露于高钾浓度20分钟，与用乙酰胆碱连续刺激20分钟相比，儿茶酚胺释放的持续时间更短。在连续暴露于钾的过程中，儿茶酚胺的释放在半对数图上呈线性下降，而乙酰胆碱引起儿茶酚胺的双相释放。先前用高钾处理过的腺体对乙酰胆碱反应不佳；然而，先前用乙酰胆碱处理过的腺体对高钾浓度表现出最大反应。高钾处理后，对乙酰胆碱的反应在20分钟内完全恢复。高钾浓度似乎仅引起“易于释放”物质的分泌，而乙酰胆碱可以作用于肾上腺中更大的儿茶酚胺储存库。