Activation of muscarinic receptors increases the concentration of free Na+ in mouse pancreatic B‐cells

FEBS Letters

Henquin, J.C.¹  Gilon, P.¹ 

[1] Unité d'Endocrinologie et Métabolisme, U CL 55.30, University of Louvain Faculty of Medicine, B-1200 Brussels, Belgium

关键词: Acetylcholine;    Cytosolic sodium;    Insulin release;    Muscarinic receptor;    Ouabain;    Pancreatic B-cell;   

DOI  :  10.1016/0014-5793(93)81193-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The fluorescent probe SBFI was used to monitor the influence of acetylcholine (ACh) on the cytosolic concentration of free Na⁺ (Na⁺ _i) in single mouse pancreatic B-cells. In the presence of 3 mM glucose and 135 mM extracellular Na⁺, Na⁺ _i, averaged 16.6 mM. ACh (100μM) increased Na⁺ _i by ~ 80%. This rise was prevented by atropine, a blocker of muscarinic receptors, and by omission of extracellular Na⁺, but still occurred if the sodium pump was blocked by ouabain. It was unaffected by tetrodotoxin, a blocker of voltage-sensitive Na⁺ channels, and was not mimicked by depolarization of the cells with high K⁺ It is concluded that activation of muscarinic receptors increases the membrane permeability to Na⁺ in pancreatic B-cells.

【 授权许可】

Unknown