Expression of angiotensin receptors and aquaporins in pregnant and non-pregnant rats. Renal expression of AT1R mRNA (A), AT2R (B & C) and AQP2 (D & E) protein and mRNA in non-pregnant (n = 23-24) and pregnant (n = 28-32) rats fed a control diet. Data are presented as mean ± SEM. Data was analysed by independent t-test. AQP2 expression was significantly decreased (P < 0.05) in pregnant versus non-pregnant controls.