Objective:To investigate effect of Glycyrrhiza uralensis on in vivo metabolites of triptolide and triptonide

disclose attenuation mechanism of G. uralensis on Tripterygium wilfordii. Method:SD rats were divided into single and combined administration groups.Combined groups were injected with triptolide or triptonide after orally treated with extracts of G. uralensis

while these single groups was injected only with triptolide or triptonide. Metabolites of triptolide or triptonide in rat plasma were identified and determinated by LC-MS/MS

and compared difference of metabolites under two administration models. Result:Four metabolites ([M+H]+

m/z 359

359

375

377) of triptolide and three metabolites ([M+H]+

m/z 375

397

413) of triptonide in rat plasma were found under two administration models

respectively;Oxydation metabolites (m/z 359 of triptolide

m/z 375 of triptonide) were the major metabolites.Another metabolite ([M+H]+

m/z 413) of triptonide in rat plasma were found only in these combined administration groups.Difference of the amount of metabolites under two administration models was significant

combined administration model was the larger. Conclusion:Under two administration models

most of metabolites of triptolide and triptonide in rat plasma were the same

while major metabolites was oxidative metabolites.G. uralensis could accelerate in vivo metabolism of triptolide and triptonide

it could provide a reference for clarifying attenuation synergistic mechanism of T. wilfordii.