Objective To explore the possible mechanism of Modified Zexie Decoction（泽泻汤加味方） in preventing high-salt induced hypertension and renal damage in rats’ model. Methods After hypertension models were established by given high-salt diet for 22 weeks

Wistar rats were randomized into the model group

the valsartan group

and high and middle dose herb groups（ n = 10 in each group）. Besides

a normal group was set（ n = 10）.From the 23 rd week

the valsartan group was given 14. 4 mg /（ kg·d） of valsartan capsule solution by gavage. High and middle dose herb groups were given 16. 2 g /（ kg·d） or 10. 8 g /（ kg·d） of Modified Zexie Decoction suspension by gavage respectively. The model group was given equivalent distilled water by gavage. The normal group was fed normally. After 8 weeks

the mRNA expressions of angiotensin Ⅱtype 1 receptor（ AT1R） and angiotensin Ⅱtype 2receptor（ AT2R） were examined. Results Compared with the normal group

the mRNA expressions of renal cortex AT1R and AT2R increased significantly in the model group（ P < 0. 01）. Compared with the model group

the mRNA expressions of AT1R and AT2R were down-regulated significantly in the valsartan group

and the high and middle dose herb groups（ P < 0. 01）. The mRNA expressions of AT1R and AT2R in the valsartan group were lower than that in high and middle dose herb groups（ P < 0. 01）. The mRNA expression of AT1R was lower

while the mRNA expression of AT2R was higher in the high dose herb group than that in the middle dose herb group（ P <0. 01）. Conclusion The effect that Modified Zexie Decoction preventing renal damage might relate to downregulating mRNA expression of AT1R and AT2R.