OBJECTIVEWuji pill is a prescription of traditional Chinese medicine(TCM) and was composed of Rhizoma Coptidis, Fructus Evodiae Rutaecarpae and Radix Paeoniae Alba. The aim of this research is to investigate the effects of Wuji pill compound with different compatibility on the levels of enzymic activity of cytochrome P450 CYP3A1/3A2 in rat liver microsomes in vitro, and to confirm the compatibility mechanism of Wuji pill from the point of relationships between compound prescription of TCM and metabolism.

METHODWith testosterone being a probe, the levels of enzymic activity of CYP3A1/3A2 were detected by HPLC, which were suppressed by Wuji pill with different compatibility in vitro.

RESULTThe IC50 of Rhizoma Coptidis, Fructus Evodiae Rutaecarpae, Radix Paeoniae Alba and 1"-9" of different level Wuji pill is: 38.96, 871.96, 15 519.17, 43.17, 60. 47, 276.12, 133.40, 118.08, 88. 47, 64. 36, 35. 13 and 39. 91 mg x L -', respectively. Rhizoma Coptidis and 1-9" of Wuji pill can suppress the enzymic activity of CYP3A1/3A2 significantly, and the capability of Rhizoma Coptidis in Wuji pill of action on CYP3A1/3A2 can be modified by different composition of Fructus Evodiae Rutaecarpae and Radix Paeoniae in Wuji pill, and there are statistical differences among the IC50 of 1#-9# of Wuji pill. While the ratio of Rhizoma Coptidis raises up in Wuji pill, Wuji pill may suppress the enzymic activity of CYP1A2 largely.

CONCLUSIONThe reason why Wuji pill with different compatibility has different pharmacodynamics and pharmacokinetics characteristics is likely to lie in the difference of the capability of Wuji pill with different compatibility on CYP3A1/3A2. [Key words] Wuji pill; CYP3A1/3A2; testosterone; HPLC; different compatibility prescription of traditional Chinese medi-cine