过刊浏览

糖皮质激素对大鼠肾上腺髓质嗜铬细胞瘤细胞ACh诱发电流的快速抑制作用

石丽君, 王春安, 陈宜张

第二军医大学基础医学部生理学教研室. 上海 200433

摘要

本研究采用全细胞膜片箝技术，以大鼠肾上腺髓质嗜铬细胞瘤细胞（PC12）为标本，观察了糖皮质激素（GC）对乙酰胆碱诱发电流（IACh）的快速作用，并初步探讨了其可能机制。结果如下：药理学鉴定表明，PC12细胞上IACh是通过烟碱受体（nAChR）引起的。箝制电压（Vh）为-80mV时，ACh（30μmol/L）诱发一内向电流；与ACh同时给予皮质酮（B，10－5mol/L）时，B对IACh的抑制作用较弱；用B（10－5mol/L）对细胞进行预处理，可提高B对IACh峰值的抑制率，这一作用可逆并呈浓度依赖性。

关键词： 糖皮质激素; 烟碱受体; 大鼠肾上腺髓质嗜铬细胞瘤细胞; 非基因组机制

Abstract

A rapid effect of glucocorticoids (GC) on acetycholine-induced current in rat phaeochromocytoma (PC12) cells and its possible mechanism were investigated by whole-cell clamp technique. The results are as follows: The acetylcholine-induced current (IACh) of PCl2 cells was proved to be generated through nicotinic ACh receptor by pharmacological identification. ACh (30 μmol/L) induced an inward current at a holding potential (Vh)of-8O mV. The inhibitory effect of corticosterone (B) on IACh was weak when 140-5 mol/L B and ACh were simultaneously applied extracellularly. Pretreatment of PC12 cells with B could augment the inhibitory effect on peak IACh, and this dose-dependent effect was reversible. At the same concentration of GC, the rank of the inhibitory potency was B > dexamethasone (Dex) > hydrocortisone (F). Extracellular application of B-BSA could also inhibit IACh rapidly.

Key words: ;;;

收稿日期：　　录用日期：

通讯作者：　　E-mail:

引用本文：

石丽君, 王春安, 陈宜张. 糖皮质激素对大鼠肾上腺髓质嗜铬细胞瘤细胞ACh诱发电流的快速抑制作用[J]. 生理学报 1998; 50 (6): .

, , . . Acta Physiol Sin 1998; 50 (6): (in Chinese with English abstract).