肉毒杆菌神经毒素F，一种VAMP特异性内肽酶，可抑制大鼠垂体细胞中钙刺激的生长激素分泌。

Botulinum neurotoxin F, a VAMP-specific endopeptidase, inhibits Ca(2+)-stimulated GH secretion from rat pituitary cells.

作者信息

Jacobsson G, Håkansson M L, Hulting A L, Meister B

机构信息

Department of Neuroscience, karolinska Institute, Stockholm, Sweden.

出版信息

Regul Pept. 1997 Jul 23;71(1):37-44. doi: 10.1016/s0167-0115(97)01017-3.

DOI:10.1016/s0167-0115(97)01017-3

PMID:9299640

Abstract

Botulinum neurotoxin F (BoNTx F) is a zinc-dependent endopeptidase that causes proteolytic cleavage of the vesicle protein VAMP (vesicle-associated membrane protein). VAMP is an important component of the molecular machinery regulating docking and fusion of secretory vesicles with the target membrane. We have investigated presence of VAMP protein in cultured rat anterior pituitary cells. Confocal laser microscopy revealed presence of VAMP-like immunoreactivity in secretory granules of GH-containing cultured rat anterior pituitary cells. Using BoNTx F, we have investigated whether VAMP is involved in growth hormone (GH) secretion. Treatment of streptolysin-O permeabilized GH-secreting cells with BoNTx F (2.0 and 20 nM) significantly inhibited Ca(2+)-induced GH release. The results show that the secretory granules of rat anterior pituitary cell contain VAMP protein and suggest that VAMP is of importance in regulating Ca(2+)-mediated GH secretion.

摘要

肉毒杆菌神经毒素F（BoNTx F）是一种锌依赖性内肽酶，可导致囊泡蛋白VAMP（囊泡相关膜蛋白）发生蛋白水解裂解。VAMP是调节分泌性囊泡与靶膜对接和融合的分子机制的重要组成部分。我们研究了培养的大鼠垂体前叶细胞中VAMP蛋白的存在情况。共聚焦激光显微镜显示，在含生长激素的培养大鼠垂体前叶细胞的分泌颗粒中存在VAMP样免疫反应性。我们使用BoNTx F研究了VAMP是否参与生长激素（GH）的分泌。用BoNTx F（2.0和20 nM）处理经链球菌溶血素-O通透处理的GH分泌细胞，可显著抑制Ca（2+）诱导的GH释放。结果表明，大鼠垂体前叶细胞的分泌颗粒含有VAMP蛋白，提示VAMP在调节Ca（2+）介导的GH分泌中具有重要作用。