Guo X, Tang X C
Shanghai Institute of Materia Medica, Chinese Academy of Sciences.
Zhongguo Yao Li Xue Bao. 1990 Jan;11(1):14-8.
In the rat tail-flick test it was shown that ip lappaconitine (LA) 1-6 mg/kg, N-deacetyllappaconitine (DLA) 4-10 mg/kg or icv DLA 20-60 micrograms/rat exhibited a dose-dependent analgesic activity, but icv LA 20-40 micrograms/rat was inactive. The analgesic potency of ip LA was a little more potent than that of DLA and slightly weaker than that of morphine (P less than 0.05). Combined ip of subanalgesic doses of morphine and LA or DLA produced significant analgesic action. Analgesia mediated by LA was not antagonized by naloxone. The analgesic effect induced by LA or DLA was abolished and restored 3 and 120 h, respectively, after ip reserpine 3 mg/kg. Concomitant administration of 1-tryptophan or 5-HT as well as premedication of alpha-methyldopa prevented reserpine-induced decrease on LA or DLA analgesia. The elevation of brain 5-HT level by icv 5-HT significantly enhanced the analgesia of LA and DLA. LA- or DLA-induced analgesia was attenuated by pretreatment of p-chlorophenylalanine but this attenuation was reversed by icv 5-HT. p-Chloroamphetamine also markedly reduced LA- or DLA-induced analgesia. It is concluded that the central serotoninergic system is involved in the modulation of LA- or DLA-induced analgesia.
在大鼠甩尾试验中发现，腹腔注射1 - 6毫克/千克的高乌甲素（LA）、4 - 10毫克/千克的去甲高乌甲素（DLA）或脑室内注射20 - 60微克/只的DLA呈现出剂量依赖性镇痛活性，但脑室内注射20 - 40微克/只的LA无活性。腹腔注射LA的镇痛效力比DLA稍强，比吗啡稍弱（P < 0.05）。亚镇痛剂量的吗啡与LA或DLA联合腹腔注射产生显著的镇痛作用。LA介导的镇痛作用不受纳洛酮拮抗。腹腔注射3毫克/千克利血平后，LA或DLA诱导的镇痛作用分别在3小时和120小时被消除并恢复。同时给予1 - 色氨酸或5 - HT以及α - 甲基多巴预处理可防止利血平引起的LA或DLA镇痛作用降低。脑室内注射5 - HT使脑内5 - HT水平升高可显著增强LA和DLA的镇痛作用。对氯苯丙氨酸预处理可减弱LA或DLA诱导的镇痛作用，但脑室内注射5 - HT可逆转这种减弱。对氯苯丙胺也显著降低LA或DLA诱导的镇痛作用。结论是中枢5 - 羟色胺能系统参与了LA或DLA诱导的镇痛调节。
