关键词：
昆虫神经毒素;酪胺;美洲(虫非)蠊;酩氨酸脱羧酶;环腺苷酸
摘 要：
本文选择美洲(虫非)蠊Periplaneta americana作为材料,采用放射性同位素标记及放射自显影技术,观察DDT中毒(虫非)蠊体内L-酪氨酸脱羧酶的变化,结果表明,DDT具有诱导酪氨酸脱羧酶活性的作用。用加入放线菌素-D及环己亚胺的方法,证明诱导控制在转录水平。还发现,这一诱导作用伴随着血淋巴中cAMP量的增加。根据DDT的诱导效应只在活体内发生,离体情况下不发生这种情况,以及连续的电刺激也可诱导毒素产生等现象,作者等提出DDT的物理诱导假说。
译 名：
STUDIES ON INSECT NEUROTOXIN: DDT INDUCTION OF TYROSINE DECARBOXYLASE IN THE AMERICAN COCKROACH
作 者：
Luo YUAN NI YI-SHENG J. T. CHANG (Department of Biology, Beijing University)
关键词：
neurotoxin——tyrosamine——Periplaneta americana——tyrosiue de-earboxylase——cAMP
摘 要：
It was previously reported that the neurotoxin released by DDT prostrate cockroaches (Periplaneta americana) was identified to be tyramine. Presumably tyramine originates from decarboxylation of tyrosine. The induction of tyrosine decarboxylases by DDT was confirmed in the present work, using 3H-tyrosine, incubated with heamolymph or nerve cord homogenates respectively and determined by liquid scintillation and autoradiography. The induction by DDT is controlled at transcriptional level, since injection of Actinomycin-D prior to DDT treatment completely abolishes the induction effect. The induction of tyrosine decarboxylase is accompanied with an increase of cAMP. However, induction only occurs in vivo, not in vitro. Based on the fact that continuous electrical stimulation also induces the production of the neurotoxin and the result of present observations, a theory of the physical induction of enzyme was hereby proposed.
