实验性自身免疫性重症肌无力运动终板处[125I]α-银环蛇毒素结合的体外定量放射自显影术

In vitro quantitative autoradiography of [125I]alpha-bungarotoxin binding at the motor end-plates of experimental autoimmune myasthenia gravis.

作者信息

Motomura M, Niwa M, Kataoka Y, Ootsuru I, Yoshimura T, Tsujihata M, Nagataki S

机构信息

Department of Internal Medicine I, Nagasaki University School of Medicine, Japan.

出版信息

Neurosci Lett. 1992 Aug 31;143(1-2):139-42. doi: 10.1016/0304-3940(92)90251-2.

DOI:10.1016/0304-3940(92)90251-2

PMID:1436658

Abstract

A quantitative evaluation was made of nicotinic acetylcholine receptors (AChR) at the motor end-plates in experimental autoimmune myasthenia gravis (EAMG). Female Lewis rats were immunized with AChR protein purified from electric organs of Narke japonica. The forelimb digit extensor muscle obtained in the chronic stage of the controls and EAMG were studied using [125I]alpha-bungarotoxin, in vitro and autoradiographically. The maximum binding capacity (Bmax) values of the controls and EAMG were calculated to be 237.7 +/- 13.0 fmol/mg (n = 4) and 42.0 +/- 4.1 fmol/mg (n = 4), respectively (P less than 0.001), and the dissociation constant (Kd) values were 11.7 +/- 1.6 nM and 7.6 +/- 0.9 nM, respectively. This in vitro autoradiographic method revealed a quantitative reduction of AChR at the motor end-plates in EAMG.

摘要

对实验性自身免疫性重症肌无力（EAMG）运动终板处的烟碱型乙酰胆碱受体（AChR）进行了定量评估。用从日本电鳐电器官中纯化的AChR蛋白免疫雌性Lewis大鼠。使用[125I]α-银环蛇毒素，通过体外放射自显影法研究了对照组和EAMG慢性期获得的前肢指伸肌。对照组和EAMG的最大结合容量（Bmax）值分别计算为237.7±13.0 fmol/mg（n = 4）和42.0±4.1 fmol/mg（n = 4）（P<0.001），解离常数（Kd）值分别为11.7±1.6 nM和7.6±0.9 nM。这种体外放射自显影方法显示EAMG运动终板处的AChR定量减少。