芫花根乙醇提取物的镇痛活性

Analgesic activity of ethanol extracts from root of Daphne genkwa

目的阐明芫花根乙醇提取物(EERD)的镇痛活性及其可能的机制。方法通过研究EERD对佐剂性关节炎(AA)大鼠的痛觉反应和足肿胀的影响;对AA大鼠炎性组织中前列腺素E2(PGE2)和白细胞介素-1β(IL-1β)的形成及SOD和过氧化氢酶(CAT)的活性的影响;血清和脑组织中NO和诱导型NO合酶(iNOS)水平的影响以及对AA大鼠c-Fos蛋白表达的影响来评价EERD的镇痛活性。结果EERD能明显减轻AA大鼠的痛觉反应和抑制足肿胀,能显著抑制炎症组织中PGE2和IL-1β的形成并提高SOD和CAT的活性,能明显降低AA大鼠脑组织中iNOS的活性从而降低NO的水平。EERD可显著抑制AA大鼠脊髓c-Fos蛋白的表达。结论EERD具有显著的镇痛作用,其镇痛机制可能是通过抑制PGE2和IL-1β的形成、降低脑组织iNOS的活性从而减少NO的生成,以及增强SOD和CAT的活性以抑制脂质过氧化反应来实现的。

Objective To elucidate the analgesic activity of the ethanol extracts from the root of Daphne genkwa （EERD）. Methods The analgesic activity of EERD was evaluated by the effects on adjuvant-induced nociceptive response and paw swelling, the formation of PGE2 and IL-1β in adjuvant arthritis （AA） rats, the activities of SOD and CAT, the levels of NO/iNOS in serum and brain tissue as well as by the effects on c-Fos protein expression in spinal cord of AA rats. Results EERD at used doses significantly delayed the adjuvant-induced nociceptive response and eased the paw swelling in AA rats. EERD also evidently inhibited the production of PGE2 and IL-1β, and enhanced the activities of SOD and CAT in the tissue of paws being injected by adjuvant. Furthermore, it remarkably reduced the content of NO and inactivated the activity of iNOS in brain tissue of AA rats. In addition, EERD at used doses exhibited promi- nent inhibition on adjuvant-induced expression of c-Fos protein in the spinal cord of AA rats. Conclusion EERD is an effective agent for analgesia. The possible mechanisms for its analgesia might be the actions of inhibiting the production of PGE2 and the release of IL-1β, reducing the activity of iNOS and hence the generation of NO in brain tissue, and blocking superoxidation through enhancing the activity of SOD and CAT.