Effect of progesterone on the expression of CFTR and AQP1 expression in peritoneal epithelial cells and OHSS symptoms in rats. Statistical comparison of WT increase (A), ascites volume (B), and pleural effusion volume (C) in PMSG-/hCG-induced OHSS rats and OHSS rats [treated with progesterone, 25 mg/d·rat; or treated with both progesterone (25 mg/d·rat) and mifepristone (diluted in corn oil, 10mg/d·rat, irrigation daily), n = 5/group]. *P < 0.05, **P < 0.01, *** P < 0.001. Western blot results showed that expression of CFTR and AQP1 proteins in peritoneal epithelial cells were suppressed by progesterone in the OHSS rats. The Pixel Value for CFTR: OHSS 1005806, OHSS+progesterone 223260, OHSS+progesterone+mifepristone 394564; The Pixel Value for AQP1: OHSS 424325, OHSS+progesterone 183016, OHSS+progesterone+mifepristone 248076; The Pixel Value for β-Actin: OHSS 821654, OHSS+progesterone 824855, OHSS+progesterone+mifepristone 823090 (D).