Fig. 1.

Total pool size analysis of renal cortical and medullary transporters and associated proteins from 0.4% NaCl normal salt (NS)- vs. 4% NaCl high salt (3 wk HS)-fed rats. Immunoblots of homogenate samples (total supernatant after low-speed centrifugation) are shown in which each lane represents a sample from an individual rat. Protein loaded/lane adjusted to ensure linearity of the detection system, assessed on each blot: 40 μg for Na⁺/H⁺ exchanger (NHE)3 and Na⁺/H⁺ exchanger regulatory factor (NHERF)-1; 20 μg for Na⁺-P_i cotransporter (NaPi)-2, Na⁺-K⁺-Cl⁻ cotransporter (NKCC2), and medullary Na⁺-K⁺-ATPase (NKA) β₁-subunit; 15 μg for dipeptidyl peptidase IV (DPPIV); 32 μg for Na⁺-Cl⁻ cotransporter (NCC) and cortical NKA β₁; 1 μg for cortical NKA α₁-subunit; 72 μg for medullary NHE3; 0.25 μg for medullary NKA α₁. Apparent molecular mass is indicated on right. Proteins were detected and quantified with the Odyssey Infrared Imaging System (Li-COR). *P < 0.05 vs. NS, assessed by paired Student's t-test.