眼镜王蛇(Ophaiophagus hannah Cantor)毒的分离及毒性组分的研究

眼镜王蛇毒用CM-C11柱层析,醋酸铵缓冲液洗脱,分出15个蛋白组分,其中组分Ⅷ、Ⅸ、Ⅻ和ⅩⅢ为毒性较大的致死组分。实验证明眼镜王蛇全毒及四个毒性组分都不具有心脏毒及突触前神经毒活性。它们阻断小鸡颈二腹肌神经肌标本对间接刺激及对外源性乙酰胆碱的反应;神经肌传递阻滞后,标本对直接刺激及对氯化钾的反应不受影响。组分Ⅸ、Ⅻ和ⅩⅢ对神经肌传递的阻滞容易逆转,组分Ⅷ则较难逆转。这四个毒性组分均为突触后神经毒,其毒力依次为Ⅷ＞Ⅸ＞Ⅻ＞ⅩⅢ,眼镜王蛇毒的主要毒性成分是突触后神经毒。

ISOLATION OF THE VENOM OF OPHIOPHAGUS HANNAH CANTOR AND STUDY OF THEIR TOXIC FRACTION

Fifteen fractions were separated from the crude venom of Ophiophagus hannah on CM-cellulose 11 column chromatography with ammonium acetate buffer by 2-stage gradient elution and purified on Sephadex G-50 column. Among them, four fractions (Ⅷ. Ⅸ, Ⅻ and ⅩⅢ) showed high lethality. These four fractions were tested in experiments, unlike cobra venom and some other elapid venoms, and exhibited no cardiotoxic and presynaptic activities. They blocked the neuromuscular transmission of the isolated chick biventer cervicis muscle and inhibited its response to Ach, but not the response to KC1. The neuromuscular block produced by fractions Ⅻ, ⅩⅢ and Ⅸ was reversible and that by fraction Ⅷ was irreversible. The Ach release on the nerve terminal was not affected and Ach dose-response curve was shifted parallelly to the right by fractions Ⅷ and Ⅸ. It is concluded that these four fractions may be regarded as postsynaptic neurotoxins.