蝎毒纯化因子Ⅱ对大鼠神经肌肉兴奋性的影响

Effects of AFSVC-Ⅱon neuromuscular excitability

雄性大鼠２１只（体重２００～２５０ｇ），随机分为Ａ、Ｂ、Ｃ三组，氨基甲酸乙酯（１ｇ／ｋｇ）腹腔麻醉，双针记录电极置于右侧股二头肌以记录肌电，双侧腋窝皮下埋藏板状电极以引导心电信号。肌电信号及心电信号，经生物信号处理系统（ＳＭＵＰ－ＰＣ）Ｚ自动记录心电幅值、频率及屈肌反射阈值、潜伏期，并进行定量分析处理。尾静脉注射蝎毒纯化因子Ⅱ（ＡＦＳＶＣ－Ⅱ）的剂量，Ａ组为４３μｇ／ｋｇ，Ｂ组为６５μｇ／ｋｇ，Ｃ组为１３０μｇ／ｋｇ，注入容量均为０．３ｍｌ。ＡＦＳＶＣⅡ注射前及注射后（每隔１０ｍｉｎ测定１次，８０ｍｉｎ停止观察）分别对上述各项生理指标进行测定。结果：ＡＦＳＶＣ－Ⅱ尾静脉注射４３～６５μｇ／ｋｇ对心电幅值没有显著影响，但注射１３０μｇ／ｋｇ１０～３０ｍｉｎ，可明显减低心电幅值；ＡＦＳＶＣ－Ⅱ尾静脉注射４３～６５μｇ／ｋｇ对屈肌反射没有显著影响，但注射１３０μｇ／ｋｇ１０～３０ｍｉｎ，可明显减低神经肌肉的兴奋性及减慢神经传导的速度。提示：蝎毒可通过抑制Ｎａ＋通道，从而明显降低神经肌肉的兴奋性。

rats were divided at random into 3(A. b.c) groups, and given abdominal anesthesia by injecting urethan(1 g/kg).Dual-needle electrode was located in the biceps femora to record myoeletricity; plate electrode was located subcutaneously in axillary fossa to record myocardioelectricity; the amplitude and frequency of myocardioelectricity,the threshold and latency of flexion reflex were recorded automatically through the biological signal translating system (SMUPPC);quantitative analysis was performed.43 μg/kg AFSVC-Ⅱ were injected through the tail vein in Group A;65 μg/kg in Group B; 130 μg/kg in Group C;the contents of injection were0.3ml. Before and after AFSVC-Ⅱ was injected, the above physiological standards were measured separately (the measuring interval was 10 min,observation was stopt in 80 min).The results demonstrated that 43～65 μg/kg AFSVC-Ⅱ injected via tail vein had no eminent effects on the amplitude of myocardioelectricity, while 130 μg/kg AFSVC-Ⅱ could markedly decrease it during 10 to 30 min; 43～65 μg/kg AFSVC-Ⅱ had no eminent effects on the flexion reflex,whereas 130 μg/kg AFSVC-Ⅱ could markedly depress the neuromuscular excitability and prolong the nerve conducting speed. The experiment provided new theoretical proof of scorpion venom binding sodium channel.