Study On Compatibility Regularity Of Drug Pair Of Platycodin And Glycyrrhiza In Pharmacodynamics (Ⅱ)

Prescriptions of TCM is the focus at present in TCM research, and also the difficult point and breakthrough point in the progress of TCM. It is important and simple to explore the compatible mechanism of Prescriptions in TCM based on the drug pair. Here the noted drug pair, Ganjie Tang, have been chosen. The anti-inflammatory and expectorant effects of the active fractions from Gangjie Tang, the saponins of Glycyrrhiza uralensis Fisch(GS) and Platycodon grandiflorum A.DC(PS), have been investigated, and the interactions between these two agents were evaluated by Jin's Q formula, modified isobolographic analysis and median-effect analysis. The study aims to quantitatively analyse drug interaction, find the intrinsic compatible law of Prescriptions, and to supply a tool for optimizing and dealing with interactions in the study of other prescriptions. Result:1 GS can ameliorate PS-induced acute toxicity. In addition, new method adapted to clinical therapeutic protocol of TCM should be used to estimate the toxicities change in any two TCMs.2 In phenol drain model, xylene-induced mouse ear edema model and PLA2-induced mouse paw edema model, co-administration of GS and PS in 8:1 can extend the duration of anti-inflammatory and expectorant effect, when compared to any agent alone. Jin's Q formula was used to evaluate the interaction of mixtures, and synergism or additivity was obtained.3 In vivo effects of GS and PS alone or combined against the mouse paw edema caused by PLA2 were observed in a dose-dependent manner. The interaction was evaluated by the three methods as above. Additivity was obtained at the effective levels by modified isobolographic analysis and median-effect analysis, whereas antagonism was indicated by Jin's Q formula.4 GS alone or combined with PS in fixed dose (0.5μg/ml) inhibited NO production in a dose-dependent manner in LPS-induced RAW 264.7 cells. Combinations of two agents, which were evaluated by Jin's Q formula, were additive at high effect levels, and synergistic at low effect levels.5 To explain the anti-inflammtory mechanism of GS or PS, we established a photometric method in vitro for screening Phospholipase A2 (PLA2) inhibitors. On the in vitro test against PLA2, GS, PS or refined PS (RPS) reduced the activity of the enzyme in a dose-dependent manner, but PS and RPS were less effective than GS. Combined effects of GS and PS in non-fixed ratio were studied using Jin's Q formula and modified modified isobolographic...