Fig. 2.

NAVR and AVR expression studies. A: Western blot analysis of purified rat kidney membrane proteins using polyclonal antibody raised against a peptide common to both NAVR and AVR: amino acids K₅₉₂DELKDEE₅₉₉ of NAVR or amino acids 168–175 of AVR detects two membrane-bound polypeptides (~100 and 50 kDa) in rat kidney membranes. Molecular mass (MM) markers (124, 80, 49, and 35 kDa) are shown on left. B: Northern blot analysis of poly(A)⁺ RNAs from different tissues. 1: RNA blot hybridized with a NAVR/AVR common probe (amino acids 1-589 of NAVR). 2: RNA blot hybridized with a NAVR-specific probe (amino acids 1–95 of NAVR). The 28S and 18S ribosomal RNAs are marked (−). Arrows indicate different-sized mRNAs detected by the common probe (1) and NAVR-specific probe (2), from the top: estimated 6 kb, 5 kb, 4 kb, 3 kb. Bracket in 1 indicates multiple mRNA sizes in kidney corresponding to 4- to 2.5-kb mRNA species. K, kidney; L, liver, H, heart, A, aorta, B, brain. C: saturation binding curves of ligand-binding studies of membrane proteins isolated from Cos1 cell transfectants expressing NAVR. ●, ¹²⁵I-ANG II; ○, [³H]AVP. Values are presented as means ± SE from 5 independent experiments.