AQP4 protein expression downregulated in large ovarian follicles (> 25 mm). (A) Western blot analysis for AQP4. Relative AQP4 protein level was determined by comparing it to β-actin level. Each bar represents the mean ± SD of four independent experiments. *p < 0.05 compared to follicles < 10 mm. (B) Immunoprecipitation assay for AQP4. Three independent experiments were performed (n = 3). Follicular cell lysates were subjected to immunoprecipitation with an anti-AQP4 antibody. The lysates were resolved by SDS-PAGE, transferred to a PVDF membrane, and immunoblotted with Anti-AQP4 antibody. Equal amounts (30 μg) of total protein were loaded on each well of the gels.