一种检测药物镇痛作用和局部麻醉作用的简便方法

A simple method for assessing analgesic activity and local anesthetic activity of drugs

４－氨基吡啶（４－ＡＰ）２．６ｍｍｏｌ·Ｌ－１０．０２ｍＬｓｃ于小鼠颈背部可引起用后足爪搔抓注射部位的反应．以４－ＡＰｓｃ后５ｍｉｎ内发生搔抓鼠数为指标，观察不同药物对它的抑制作用．麻醉性镇痛药吗啡，哌替啶和芬太尼能明显抑制这一反应；弱镇痛药罗通定，安乃近，水杨酸钠和非镇痛药无效．局部麻醉药普鲁卡因，利多卡因或丁卡因与４－ＡＰ混合ｓｃ也可取消搔抓反应．结果表明这一方法可用于检测麻醉性镇痛药的镇痛作用和局麻药的局部麻醉作用．

Subcutaneous injection of 0.02 mL of 4 aminopyridine (4 AP, 2.6 mmol·L 1 ) into the dorsal surface of the neck was used as a nociceptive stimulus which caused the mouse to scratch the injected site by the hindpaws. Effects of various analgesics and other related drugs on this behavior were determined by counting the number of mice with scratching response within 5 min after injection of 4 AP. The narcotic analgesics morphine (10 mg·kg 1 , sc), pethidine (25 mg·kg 1 , sc) and fentanyl (0.14 mg·kg 1 ) inhibited the scratching response markedly. The mild analgesics rotundine, analgine, sodium salicylate and the nonanalgesics were inactive. Local anesthetics procaine (0.25%), lidocaine (0.1%) or tetracaine (0.01%) coinjected sc with 4 AP also abolished the scratching behavior. When procaine and 4 AP were injected sc into two separated sites, no effect on scratching response was observed. The results suggest that the inhibition of 4 AP induced scratch may provide a simple method for assessing analgesic activity and local anesthetic activity of drugs.