Objective: To study effect of Danggui Shaoyao San (DSS) on aquaporin-2(AQP2) expression in the kidney of rats with cirrhosis ascites

and explore the mechanism. Method: Healthy male SD rats were randomly divided into 6 groups:normal

model

glycyrrhizin(0.052 5 g·kg-1)

low

middle and high dose group of DSS(4.3

8.6

17.2 g·kg-1). After 1 week

except the normal group

the other rats were given 35% phenobarbital solution as drinking water

after 1 weeks normal water was recoveried

and the model was established by intraperitoneal injection of CCl4:at the 2-3 weeks 12% CCl4 oil solution was given

next two weeks 14% was given

then 16% was given until 14th week

twice a week

the volume being 10 mL·kg-1

the normal group was given equal volume of saline. At the same time

the treatment group was orally given corresponding drugs until 13th week. Then metabolic cages were used to collect urine in 24 hours for measuring the urine volume. The filter paper was used to absorb ascites.The immunohistochemistry was used to detect the expression of vasopressin Ⅱ style receptor (V2R) and AQP2 of kidney. The protein expression of V2R and AQP2 was detected by Western blotting. Result: Compared with the model group

in model group rats 24 h urine volume decreased significantly

the amount of ascites was significantly increased (P<0.05). Compared with the model group

urine volume significantly increased in 24 hours and the amount of ascites decreased differently in groups of DSS (P<0.05)

the expression of V2R was significantly increased in rat kidney

kidney tissue AQP2 expression increased. Conclusion: DSS up-regulate the expression of AQP2 in the kidney of rats with cirrhosis ascites

which may be one of the mechanisms.