Objective To observe the changes of renal function and histomorphology in rats treated with aristolochiae manshuriensis（AM）

Longdanxiegan Decoction（LD） and Modified Longdanxiegan Decoction（MLD

removed angelica sinensis

rehmannia dride rhizome and glycyrrhizae uralensis）.Method All SD rats were randomly divided into the normal control group（group 1）

AM group（group 2）

LD group（group 3） and MLD group（group 4）.Group 1 was given distilled water orally for 8 weeks

and group 2

3 and 4 were given respectively AM（6 g/kg）

LD（17.5 g/kg

containing AM 6 g/kg） and MLD（14.5 g/kg

containing AM 6 g/kg） all for 8 weeks.The biochemical indexes in serum and urine

and renal histomorphological changes in rats were detected at the end of 8th week.Result In group 2

3 and 4 the rats all had significant renal lesion

which was the most serious in group 2

and less in group 3

but in group 4 the renal lesion was serious too and some indexes was even higher than those in group 2.Conclusion AM

LD and MLD all can induce the renal lesion and MLD has stronger nephrotoxicity.It suggests that the toxicity of formulas containing AM is not as the same as that of AM.Angelica sinensis

rehmannia dride rhizome and glycyrrhizae uralensis contained in LD may inhibit the nephrotoxicity of AM.