Analgesic effects of Shaoyao Gancao Tang and the correlation between analgesic effects and compatibility proportion

Objective: To use the combination of nine herbal extracts as an alternative medicine of Shaoyao Gancao Tang(SGT) and analyze the correlation between analgesic effects and compatibility proportion. Methods: Kunming rats were randomly divided into control group, Aspirin group, and SGT group. Aspirin(10mg/kg), SGT(10, 20, 30mg/kg) were administered by oral gavage. Results: In hot plate test, SGT-Ⅰ and SGT-Ⅱ at 10, 20 and 30mg/kg doses produced significant analgesic effects in 60 th, 90 th and 120 th minute(P0.05, compared with control values). SGT-Ⅲ at 10mg/kg doses had no analgesic effect in both 60 th and 120 th minutes and it also had no analgesic effects at 20mg/kg in 120 th minute(compared with control values). In acetic acid writhing test, SGT-Ⅰ and SGT-Ⅱ produced significant analgesic effects at 10, 20 and 30mg/kg doses(P0.05, compared with control values). SGT-Ⅲ had analgesic effects only at 30mg/kg(P0.05, compared with control values). There was a dosedependent relationship between analgesic effects and the administered dosage of SGT-Ⅰ and SGT-Ⅱ at 10, 20 and 30mg/kg doses in 60 th, 90 th and 120 th minutes in both hot plate test and acetic acid writhing test. Conclusion: In this study, we have shown that SGT-Ⅰ, SGT-Ⅱ and SGT-Ⅲ produced analgesic effect. SGT-Ⅰ and SGT-Ⅱ have the same compatibility proportion and they has produced an equal analgesic effect. SGT-Ⅱ and SGT-Ⅲ have different compatibility proportion and they producs different analgesic effect. The study indicates that the combination of nine herbal extracts can be used as an alternative medicine of SGT.