- 作者： 張傳炯; 蘇銘嘉
- 作者服務機構： 國立臺灣大學醫學院藥理學研究所
- 中文摘要：
南美響尾蛇毒之 Crotoxin 乃作用於運動神經末端之鍵
前神經毒素，由酸性多? Crotapotin 及鹼性磷脂?構成。
Crotapotin 本身無磷脂?活性，並不加強磷脂?活性，亦
缺少神經毒性。磷脂?甲本身即只有 Crotoxin 一成以下之
神經毒活性，磷脂?甲以離體小鼠橫膈膜處理時其神經毒性
於30分鐘內消失94%，但 Crotapotin 同時存在時卻無任何
活性之消退。無橫膈膜時磷脂?甲單獨亦減弱54%，由上可
結論 Crotapotin在 Crotoxin中之角色乃為，「Chaperone」
即保護磷脂?甲不受非特異性結合及破壞，護送其順利到達
作用點即神經末端結合產生作用。d - 英文摘要： Crotoxin complex, isolated from the venom of South American rattlesnake, is a presynap-tic neurotoxin composed of a basic phospholipase A and an acidic subunit crotapotin. Cro-tapotin alone does not hydrolyse phospholipids, nor activate the enzyme activity of phospho-lipase A and has no neuromuscular blocking activity. Phospholipase A alone is 10 times lesspotent in blocking the neuromuscular transmission than crotoxin. When incubated in vitro withan isolated mouse diaphragm, phospholipase A loses 94% neurotoxicity in the absence of cro-tapotin in 30 min. No loss of activity can be detected if incubated with crotapotin. Whenincubated alone without the diaphragm, phospholipase A also loses 54% of neurotoxicity. Itis concluded that crotapotin functions as‘chaperone’sharpening the specificity by decreasingthe non-specific binding and increasing the stability of the toxic phospholipase A so as tominimize distraction and destruction en route to the nerve ending.
- 中文關鍵字： --
- 英文關鍵字： --
