Bittner M A, Habig W H, Holz R W
Department of Pharmacology, University of Michigan Medical School, Ann Arbor 48109-0626.
J Neurochem. 1989 Sep;53(3):966-8. doi: 10.1111/j.1471-4159.1989.tb11800.x.
Previous work indicates that the heavy chain of tetanus toxin is responsible for the binding of the toxin to the neuronal membrane and its subsequent internalization. In the present study, the light chain of tetanus toxin mimicked the holotoxin in inhibiting Ca2+-dependent secretion of [3H]norepinephrine from digitonin-permeabilized adrenal chromaffin cells. Preincubation of tetanus toxin with monoclonal antibodies to the light chain prevented the inhibition by tetanus toxin. Preincubation of tetanus toxin with nonimmune ascites fluid or with monoclonal antibodies directed against the C fragment (the C-terminal of the heavy chain) or the heavy-chain portion of the B fragment did not prevent inhibition by tetanus toxin. The data indicate that the light chain is responsible for the intracellular blockade of exocytosis.
先前的研究表明，破伤风毒素的重链负责毒素与神经元膜的结合及其随后的内化。在本研究中，破伤风毒素的轻链在抑制洋地黄皂苷通透的肾上腺嗜铬细胞中[3H]去甲肾上腺素的钙依赖性分泌方面模拟了全毒素。用抗轻链单克隆抗体预孵育破伤风毒素可防止破伤风毒素的抑制作用。用非免疫腹水或针对C片段（重链的C末端）或B片段的重链部分的单克隆抗体预孵育破伤风毒素并不能防止破伤风毒素的抑制作用。数据表明轻链负责细胞内胞吐作用的阻断。
