Ciguatoxin is a novel type of Na+ channel toxin.
Ciguatoxin is a novel type of Na+ channel toxin.
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雪卡毒素是一种新型Na通道毒素。
DOI：
10.1016/s0021-9258(17)39735-1
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发表时间：
1984
期刊：
影响因子：
--
通讯作者：
M. Lazdunski
中科院分区：
文献类型：
--
作者：
Jean;H. Vijverberg;Christian FrelinS;Eliane Chunguell;Anne;Raymond BagnisII;M. Lazdunski
0.1 ~ 10 ng/ml的纯化雪卡毒素抑制脑突触体神经递质（γ -氨基丁酸和多巴胺）的净积累。这种作用是由于神经递质释放的刺激。在0.62纳克/毫升时观察到毒素的半最大效应。河豚毒素（K0.5 = 4 nM）完全抑制了雪卡毒素的作用。神经母细胞瘤细胞的电生理研究表明，雪卡毒素诱导膜去极化，而这是由河豚毒素阻止的，这是由于其增加Na+通透性的作用。在适当的条件下，雪卡毒素在膜极化水平和重复动作电位中产生自发振荡。当雪卡毒素与蛇曲霉碱、蛇曲霉毒素、拟除虫菊酯、海葵或蝎子毒素协同使用时，可刺激22Na+通过神经母细胞瘤细胞和大鼠骨骼肌母细胞的电压依赖性Na+通道进入。在缬曲定存在的情况下，雪卡毒素对22Na+通量的半最大影响发生在浓度为0.5 ng/ml时。雪卡毒素对22Na+通量的刺激被河豚毒素所消除。这些结果表明，雪卡毒素属于作用于Na+通道的一类新的毒素。
Purified ciguatoxin at 0.1 to 10 ng/ml inhibits the net accumulation of neurotransmitters (gamma-aminobutyric acid and dopamine) by brain synaptosomes. This action is due to a stimulation of neurotransmitter release. The half-maximum effect of the toxin is observed at 0.62 ng/ml. The effect of ciguatoxin is completely inhibited by tetrodotoxin (K0.5 = 4 nM). Electrophysiological studies on neuroblastoma cells indicate that ciguatoxin induces a membrane depolarization which is prevented by tetrodotoxin and which is due to an action that increases Na+ permeability. Under appropriate conditions ciguatoxin creates spontaneous oscillations in the membrane polarization level and repeated action potentials. Ciguatoxin stimulates 22Na+ entry through the voltage-dependent Na+ channels of neuroblastoma cells and rat skeletal myoblasts when it is used in synergy with veratridine, batrachotoxin, pyrethroids, sea anemone, or scorpion toxins. The half-maximum effect of ciguatoxin on 22Na+ flux in the presence of veratridine occurs at a concentration of 0.5 ng/ml. Stimulation of 22Na+ flux by ciguatoxin is abolished by tetrodotoxin. These results taken together indicate that ciguatoxin belongs to a new class of toxins acting on Na+ channels.