Mechanism of increase in negative after‐potential by dicophanum (DDT) in the giant axons of the cockroach *
Mechanism of increase in negative after‐potential by dicophanum (DDT) in the giant axons of the cockroach *
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蟑螂巨轴突中双酚 (DDT) 增加负后电位的机制 *
DOI：
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发表时间：
1960
期刊：
影响因子：
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通讯作者：
T. Yamasaki
中科院分区：
文献类型：
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作者：
T. Narahashi;T. Yamasaki
已经有人试图了解敌敌畏(DDT)是否会引起神经后电位的变化。蟹神经的负后电位只有轻微的增加(Shanes，1949b)，而鱿鱼和青蛙的神经则没有变化(Shanes，1949a，1951)。另一方面，我们以前的研究发现，滴滴涕可引起蟑螂神经负后电位的显著增加和延长(Yamasaki&Ishii，1952；Yamasaki&Narahashi，1957b，c，d)。滴滴涕的这种效应及其不稳定作用被认为是滴滴涕毒性作用的最重要特征(例如Roeder&Weant，1948；Welsh&Gordon，1947；Yamasaki&Ishii，1954)。然而，没有足够的证据来解释滴滴涕引起的负后电位增加。正如鱿鱼巨型轴突(Frankenhaeuser&Hodgkin，1956)和兔的无髓神经纤维(Greengard&Straub，1958)一样，正常蟑螂巨型轴突的负后电位可以通过神经膜附近释放的钾离子的积累来解释(Narahashi&Yamasaki，1960)。本文给出了实验结果，旨在阐明DDT引起负后电位增加的机理。
Attempts have already been made to see whether dicophanum (DDT) causes changes in after-potentials in nerve. In crab nerve there was only a slight increase in negative after-potential (Shanes, 1949b), whereas no change was observed in squid and frog nerves (Shanes, 1949a, 1951). On the other hand, it was found in our previous studies that DDT causes a marked increase and prolongation of the negative after-potential in cockroach nerve (Yamasaki & Ishii, 1952; Yamasaki & Narahashi, 1957b, c, d). This effect of DDT, together with its unstabilizing action, is regarded as the most important feature of the toxic action of DDT (e.g. Roeder & Weiant, 1948; Welsh & Gordon, 1947; Yamasaki & Ishii, 1954). However, there is no adequate evidence to explain the increase in negative afterpotential caused by DDT. As in squid giant axons (Frankenhaeuser & Hodgkin, 1956) and in nonmyelinated nerve fibres of the rabbit (Greengard & Straub, 1958), the negative after-potential of normal cockroach giant axons has been demonstrated to be explicable by an accumulation of the released potassium ions in the immediate vicinity of the nerve membrane (Narahashi & Yamasaki, 1960). The present paper gives the results of experiments whose aim was to elucidate the mechanism of the increase in negative after-potential brought about by DDT.