Starkus J G, Narahashi T
Am J Physiol. 1978 Nov;235(5):C204-11. doi: 10.1152/ajpcell.1978.235.5.C204.
A variety of excitable and inexcitable preparations have been examined for their sensitivity to the depolarizing action of alpha-dihydrograyanotoxin II. alpha-Dihydrograyanotoxin II was effective in producing membrane depolarization in giant axons from the crayfish (Procambarus clarki) and sartorius muscle fibers from the frog (Rana pipiens) and the salamander (Taricha torosa). The toxin-induced depolarization was reversed by lowering the external sodium concentration. High concentrations of tetrodotoxin and saxitoxin were also effective in reversing the depolarization in the various grayanotoxin-sensitive preparations studied except in the salamander sartorius muscle, in which sodium-dependent action potentials were highly resistant to tetrodotoxin and saxitoxin. In contrast, alpha-dihydrograyanotoxin II was ineffective in changing the resting membrane potential in the muscle fibers of the crayfish (Procambarus clarki and Orconectes virilis) and in the salivary gland giant cells from Drosophila virilis. Of the preparations that were examined, only the membranes that produce a sodium-dependent action potential are sensitive to the depolarizing action of alpha-dihydrograyanotoxin II.
已经对多种可兴奋和不可兴奋的标本进行了检测，以研究它们对α-二氢灰毒素II去极化作用的敏感性。α-二氢灰毒素II可有效使小龙虾（克氏原螯虾）的巨轴突、青蛙（豹蛙）和蝾螈（粗皮渍螈）的缝匠肌纤维发生膜去极化。通过降低细胞外钠浓度可逆转毒素诱导的去极化。高浓度的河豚毒素和石房蛤毒素也能有效逆转所研究的各种对灰毒素敏感的标本中的去极化，但蝾螈缝匠肌除外，在该标本中钠依赖性动作电位对河豚毒素和石房蛤毒素具有高度抗性。相比之下，α-二氢灰毒素II对小龙虾（克氏原螯虾和 virilis螯虾）的肌纤维以及果蝇的唾液腺巨细胞的静息膜电位没有影响。在所检测的标本中，只有产生钠依赖性动作电位的膜对α-二氢灰毒素II的去极化作用敏感。
