【摘要】 目的研究中华眼镜蛇神经毒素(NT)的镇痛活性和对离体蛙腹直肌N2-AChR的拮抗作用。方法采用三种模型(电刺激-嘶叫法,热板法,醋酸扭体法)观察NT的镇痛活性,并观察NT对ACh所致蛙离体腹直肌收缩的影响。结果 NT能提高电刺激-嘶叫法,热板法的痛阈,抑制醋酸引起的扭体次数。NT镇痛具有剂量-效应关系,给药后2 h起效,5 h达峰。NT能使ACh引起的蛙腹直肌收缩的量效曲线平行右移。结论 NT对三种致痛模型均有确切的镇痛活性,NT对N2-AChR的拮抗作用为竞争性拮抗。更多还原

【Abstract】 Objective To study the analgesic effect and the drug- receptor interactions with frog rectus abdominis N2- receptor of the neurotoxin from Naja atra venom( NT). Methods Three model of pain( tail electric stimulation- vocalization test,the hot- plate test,and writhing responses in mice) were used. The effects of NT on acetylcholine- induced isolated frog rectus abdoninis were observed. Results NT could dose- dependently raise the pain threshold in hot- plate test in mice and inhibit the writhing reaction induce by acetic acid in mice. The analgesic effect of NT effect at 2 h and peaked at 5 h. NT produced a concentration- dependent parallel shift to the right of dose- response curve of acetylcholine applied exogenously with no change in the maximal asymptotic response. Conclusion NT had a better analgesic effect on the pain due to hot- plate,acetic acid and electric stimulation. NT was determined as the competitive antagonists of N2-AChR.更多还原