Volume 59, Issue 5, Pages 1881-1890 (May 2001) Coordinate regulation of canine glomeruli and adrenal angiotensin receptors by dietary sodium manipulation  Wei Zheng, Hong Ji, Zsolt Szabo, Phillip R. Brown, Sung-Eun Yoo, Kathryn Sandberg  Kidney International  Volume 59, Issue 5, Pages 1881-1890 (May 2001) DOI: 10.1046/j.1523-1755.2001.0590051881.x Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 1 Effect of dietary sodium manipulation on parameters of the renin-angiotensin system (RAS). Blood was removed from animals in the High salt (□) and Low salt (▪) groups and analyzed for plasma levels of renin (A), Ang II (B), aldosterone (C), and corticosterone (D). Data are expressed as the means ± SEM from assays performed in triplicate. N = 4 per group. Kidney International 2001 59, 1881-1890DOI: (10.1046/j.1523-1755.2001.0590051881.x) Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 2 125I-[Sar1,Ile8]Ang II binding to kidney and adrenal canine angiotensin II subtype 1 (cAT1) receptors. (A) Time course. Isolated kidney glomeruli (•) and membranes prepared from renal medulla (▪) and the adrenal gland (○) were incubated for different times with 500 pmol/L 125I-[Sar1,Ile8]Ang II at 27°C. Values are the means ± SEM from three independent experiments performed in duplicate. (B) Dose response curve. Isolated kidney glomeruli (•) and membranes prepared from the renal medulla (▪) and adrenal gland (○) were incubated with 500 pmol/L 125I-[Sar1,Ile8]Ang II and increasing concentrations of membranes ranging from 5 to 30 μg protein per sample for 120 minutes at 27°C. Values are the means ± SEM from three independent experiments performed in triplicate. Kidney International 2001 59, 1881-1890DOI: (10.1046/j.1523-1755.2001.0590051881.x) Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 3 Competition binding profiles of angiotensin ligands for dog AT receptors expressed in kidney and adrenal tissues. The binding profiles of Ang II (○), L-163,017 (▴), SK31080 (•), losartan (□), and PD-123,319 (♦) are shown for isolated kidney glomeruli (A), and membranes prepared from renal medulla (B) and the adrenal gland (C). Samples were incubated with 500 pmol/L 125I-[Sar1,Ile8]Ang II and increasing concentrations of unlabeled competitor ligands. The x axis represents the log concentration (mol/L) of unlabeled competitor ligands, and the y axis represents the binding expressed as a percentage of the specific binding obtained in the absence of competitor. Each point represents the mean of specific binding data from three separate experiments carried out in triplicate. (Inset) The binding profile of PD-123,319 for adrenal membranes under conditions in which all the cAT1 receptors are blocked with losartan (10 μmol/L) is shown. Kidney International 2001 59, 1881-1890DOI: (10.1046/j.1523-1755.2001.0590051881.x) Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 4 Saturation analysis of dog AT receptors expressed in kidney and adrenal tissues. Saturation curves of AT receptors for isolated kidney glomeruli (A), and membranes prepared from renal medulla (B) and the adrenal gland (C and D). Samples were incubated with increasing concentrations of 125I-[Sar1,Ile8]Ang II in the presence of saturating concentrations of the AT2 receptor blocker PD-123,319 in the presence and absence of 200 nmol/L Ang II. Symbols are: (▪ high salt; (▴) low salt. The x axis represents the concentration (nmol/L) of [Sar1,Ile8]-Ang II, and the y axis represents the percentage specific binding. Each point represents the mean of specific binding data from three separate experiments carried out in duplicate. (Insets) Scatchard plots from saturation binding data are shown. Kidney International 2001 59, 1881-1890DOI: (10.1046/j.1523-1755.2001.0590051881.x) Copyright © 2001 International Society of Nephrology Terms and Conditions

Figure 5 Shown are cAT1 and cAT2 receptor Bmax values calculated from Scatchard plots for isolated kidney glomeruli and membranes prepared from renal medulla and the adrenal gland in the high-salt (H; □) and low-salt (L; ▪) animal groups. Data are expressed as the means ± SEM of Bmax values determined from Scatchard plots as in Figure 4. N = 6 per group. Kidney International 2001 59, 1881-1890DOI: (10.1046/j.1523-1755.2001.0590051881.x) Copyright © 2001 International Society of Nephrology Terms and Conditions