Objective: To observe effects on attenuated toxicity of Tripterygii Radix et Rhizoma(LGT) by compatibility with Lysimachiae Herba(JQC)

screen out the best proportion between them and give preliminary evaluation of its chemical contribution. Method: The best proportion in the toxicity-attenuated effects of LGT by compatability with JQC was screened out by principal component analysis(PCA) in the subacute toxicity test of mice orally administrated for 14 consecutive days

then such effect at the best proportion was evaluated in the conventional acute toxicity test of mice

and finally its contribution of the chemical difference characteristic components to overall efficacy was assessed by the gray correlation analysis(GCA). Result: Compared with the normal group

LGT alone group significantly elevated serum biochemical markers

including alanine aminotransferase(ALT)

aspartate aminotransferase(AST)

creatinine(Cr) and urea nitrogen(BUN) levels

malondialdehyde(MDA) levels in the liver and kidney tissues

as well as the overall efficacy of Z value(P<0.01).Compared with LGT alone group

the combined groups of LGT and JQC significantly reduced LGT-induced excessively high levels of ALT when the mass ratio was 2:1

1:1

1:2 or 1:4(P<0.05

P<0.01)

those of serum AST

Cr

BUN

liver MDA and Z value when the ratio was 4:1

2:1

1:1

1:2 or 1:4(P<0.05

P<0.01)

and those of kidney MDA when the ratio was 4:1

2:1 or 1:1(P<0.05

P<0.01).The overall efficacy of Z values of LGT and JQC in the mass ratios including 4:1

1:1

1:2 and 1:4 was significantly higher than that in the ratio of 2:1(P<0.01).The half lethal dose(LD50) of the LGT alone was 517 mg·kg-1

while that of the LGT-JQC(2:1) ratio group increased to 889 mg·kg-1 with an increase of 72%.The gray correlation coefficients of 12 chemical compositions with different characteristics produced before and after the compatibility and its overall efficacy Z value

the largest of which was triptolide(TP). Conclusion: LGT combined with JQC in the mass ratio of 4:1-1:4 attenuates LGT-induced subacute hepatotoxicity and nephrotoxicity

and the best ratio of such effect is 2:1.At the best ratio of 2:1

acute toxicity and subacute toxicity decrease by 72% and 138.5%

respectively.Triptolide is the most important chemical component that causes the attenuated effect of LGT combined with JQC.