Rat tissue extract (50 μg) was separated by 15% SDS-PAGE, and the membranes were blotted with Aquaporin 2 antibody (GTX132089) diluted at 1:500 and competitor's antibody (SC-9882) diluted by 1:100. The HRP-conjugated anti-rabbit IgG antibody (GTX213110-01) was used to detect the primary antibody.