To　test　the　effect　on　human　pregnane　X　receptor　(hPXR)-mediated　transcription　regulation　of　CYP　3A　4　by　selected　anti-hyperglycemic　agents,　transient　cotransfection　reporter　gene　assays　in　HepG2　cells　were　performed　with　the　hPXR　expression　plasmid　and　the　reporter　gene　plasmid　which　contains　XRE　in　the　promoter　of　CYP　3A　4　linked　to　luciferase.　In　the　dose-effect　study,　wu　wei　zi　(Schisandra),　niu　pang　zi　(Burdock),　ju　luo　(Juluo)　and　Mitiglinide　induced　the　CYP　3A　4　transcription　via　PXR　in　an　evident　dose-dependent　manner,　but　other　anti-hyperglycemic　agents　in　this　experiment　did　not.　In　the　time-effect　study,　wu　wei　zi,　niu　pang　zi,　ju　luo　and　Mitiglinide　induced　CYP　3A　4　transcription　between　12　h　and　36　h,　the　strongest　induction　appeared　in　36　h.　So　three　herb　extracts,　wu　wei　zi,　niu　pang　zi,　Ju　luo　and　Mitiglinide　stimulate　the　PXR-mediated　transcription　of　CYP　3A　4.　Other　anti-hyperglycemic　agents　in　this　experiment　have　no　effect　on　the　CYP　3A　4　transcription　via　PXR.