原矛头蝮蛇毒毒性及恢复规律

目的:对原矛头蝮(P.mucrosquamatus)的毒性及其恢复规律进行考察,增进对该蛇毒性的认识。方法:用该蛇连续攻击小鼠,用梯度剂量蛇毒对小鼠进行腹腔注射,统计死亡率,以折算绝对毒性和半数致死量。对毒性耗竭个体,在梯度时间间隔采集蛇毒,以考察毒性恢复规律。结果:原矛头蝮在2 h内可导致6只小鼠死亡。蛇毒对小鼠的半数致死量为12.204μL/Kg。毒性耗竭后,在间隔21天所获得蛇毒的容积达到最大值即190μL,湿重为149.7 mg。结论:毒蛇在攻击猎物时,并不一次性排完毒腺中的所有毒液,随着攻击次数的增多,毒腺中毒液量逐步减少直至耗竭。其毒液量的恢复需要约3周时间,期间,单次排毒量逐渐增加,干物质的含量也基本呈递增趋势。就单次最大排毒量而言,原矛头蝮高于竹叶青、蝮蛇和银环蛇。其单位剂量毒性高于五步蛇和竹叶青。

Toxicity and Recovery of Protobothrops Mucrosquamatus Venoms

Objective:To enhance the comprehending of the toxicity of P. mucrosquamatus, the researches on toxicity and recovery of the snake''s venom were carried out.Methods:Conducting a continuous attack experiment on mice with the snake, using intraperitoneal injection on mice with the venom in dose gradients and counting mortality, then the absolute toxicity and median lethal dose (LD 50) of the snake could be calculated. As for the individuals of toxicity depletion experiment, their venom were collected in gradient time interval to investigate the regulation of toxicity recovery.Results:After the continuous attack, six mice have died in two hours. The median lethal dose (LD 50) of P. mucrosquamatus to mice is 12.204 uL/Kg. After the toxicity depletion, the maximum of venom volume was obtained in 21 days interval and that is 190 uL. The wet weight is 149.7 mg.Conclusion:When venomous snakes attack prey, they do not have to discharge the whole venom from the venom gland at once time. With the increased attacks, the volume of remaining venom in the venomgland gradually decreases till up to depletion. The time of toxicity recovery always needs about three weeks and during this time, the volume of single discharging venom increases gradually. The content of dry matter in venomalso shows an increasing trend. As for the maximum of single discharging venom, P. mucrosquamatus is higher than T. stejnegeri, A.blomhoffii and B. multicinctus. The toxicity of unit dose is also higher than that in D. acutus and T. stejnegeri.