目的研究野罌粟總生物堿(TAPN)的鎮(zhèn)痛作用與前列腺素(PGs)、阿片受體的關(guān)系.方法采用小鼠熱板法、扭體法、電刺激法3種致痛模型;測(cè)定3種不同致痛物乙酰膽堿(Ach)、醋酸(AA)和硫酸鎂(MgSO₄)致小鼠扭體反應(yīng)后腹腔液中前列腺素E₂(PGE₂)水平及采用納洛酮拮抗實(shí)驗(yàn)的方法,分析TAPN鎮(zhèn)痛作用與前列腺素及阿片受體的關(guān)系,初步探討TAPN的鎮(zhèn)痛作用機(jī)制.結(jié)果TAPN對(duì)Ach、AA誘導(dǎo)的小鼠扭體反應(yīng)的抑制作用明顯強(qiáng)于對(duì)MgSO₄ 的作用,且TAPN能明顯降低小鼠AA致扭體后腹腔液中PGE₂水平;在納洛酮拮抗實(shí)驗(yàn)中,ip或側(cè)腦室給藥(icv)阿片受體拮抗劑納洛酮均不能對(duì)抗TAPN的鎮(zhèn)痛作用.結(jié)論TAPN抑制PGs的合成,可能是其發(fā)揮外周鎮(zhèn)痛作用的主要機(jī)制;其中樞鎮(zhèn)痛作用與阿片受體無(wú)關(guān).

Objective To study the relationship between analgesic effect of total alkaloids inPapaver nudicaule(TAPN)and prostag-landins (PGs)with opium receptors.Methods The analgesic effect of TAPN was studied by hot-plate,writhing,electric-evoked methods of mice.The analgesic mechanisms of TAPN and PGs with opium receptors were studied by the writhing numbers induced by diffe-rent substances (Ach,AA,MgSO₄),the PGE₂ level in celiac fluid in mice after treated by AA writhing test and the antagonistic experiment of Naloxone.Results The inhibitory effect of TAPN on the writhing induced by Ach and AA in mice was stronger than that induced by MgSO₄.TAPN could also lower the PGE₄level in celiac fluid.In the antagonis-tic experiment of Naloxone,no antagonism to the analgesic effect of TAPN had been found by ip or icv Naloxone.Conclusion It may be the mainly peripheral analgesic mechanism that TAPN could lower the PGE₂level in celiac fluid.Its central analges-ic mechanisms are not related to opium receptors.