[Effect of Esculentoside A on Expression of AQP2 and AQP4 Protein of Kidney in Water-Loaded Rats].

OBJECTIVE: To observe the regulatory effect of Esculentoside A (EsA) on urination and the expression of AQP2 and AQP4 protein of kidney in water-loaded rats, and to discuss its mechanism of diuresis. METHODS: 50 male SD rats were randomly divided into five groups, including blank control group, hydrochlorothiazide group (0.4 mg/kg) and EsA high, middle and low dose groups (5.2, 2.6 and 1.3 mg/kg, respectively). After intraperitoneally injecting of different concentrations of EsA, urinary amount of model rats in continuous six hours was measured. Then the expression of AQP2 and AQP4 protein and mRNA of kidney were detected by immunohistochemistry method and Real-Time quantitative PCR. RESULTS: Compared with blank control group, the expression of AQP2 and AQP4 protein and mRNA of kidney were significantly reduced as well as the urinary amount was significantly increased in EsA high dose group (P < 0.05), while the expression of AQP2, AQP4 protein and mRNA of kidney as well as urinary amount had no obvious difference in EsA middle and low dose groups. CONCLUSION: 5.2 mg/kg of EsA can reduce the expression of AQP2 and AQP4 protein and mRNA of kidney and the reabsorption of water, which results in diuresis.