Post hoc comparison of the intrarenal and circulating renin‐angiotensin(‐aldosterone) systems in cats with ischemia‐induced chronic kidney disease

FIGURE 1. Overview of original studies from which the groups evaluated in the present study were generated: Unilateral renal ischemia (RI, n = 6; top panel); unilateral renal ischemia followed by delayed contralateral nephrectomy (RI‐DCN, n = 5; middle panel); and the healthy control group (n = 8; bottom panel). Lourenço, B. (nd). Circulating and intrarenal RA(A)S study. Created in BioRender. https://BioRender.com/wf37jn7.

FIGURE 2. Dot plots of plasma renin activity (PRA; log‐transformed) and indirect systolic arterial blood pressure (BP; mmHg) before and 180 days after surgically induced ischemic renal injury in cats of the RI group (n = 6). Data from the same individual are connected by solid lines.

FIGURE 3. Dot plots of log‐transformed plasma renin activity (PRA), log‐transformed urinary aldosterone‐to‐creatinine ratio (UACR), and direct systolic arterial blood pressure (BP; mmHg) over the study period in cats of the RI‐DCN group (n = 5). Data from the same individual are connected by solid lines.

FIGURE 4. Dot plots of log‐transformed serum angiotensin peptide and aldosterone equilibrium concentrations by study group. Data from the control, RI, and RI‐DCN group are plotted as blue circles, green squares, and magenta triangles, respectively. Ang, angiotensin; RI‐DCN, unilateral renal ischemia followed by delayed contralateral nephrectomy; RI, unilateral renal ischemia.

FIGURE 5. Dot plots of log‐transformed circulating renin‐angiotensin‐aldosterone system surrogate indices by study group. Data from the control, RI, and RI‐DCN group are plotted as blue circles, green squares, and magenta triangles, respectively. AA2, aldosterone‐to‐angiotensin II ratio; ACE‐S, surrogate for angiotensin‐converting enzyme activity; PRA‐S, surrogate for plasma renin activity; RI‐DCN, unilateral renal ischemia followed by delayed contralateral nephrectomy; RI, unilateral renal ischemia.

FIGURE 6. Dot plots of log‐transformed renal tissular angiotensin peptide equilibrium concentrations by group and kidney. Data from the control, RI, and RI‐DCN group are plotted as blue circles, green squares, and magenta triangles, respectively. Ang, angiotensin; IK, ischemic kidney; NIK, non‐ischemic kidney; RI, unilateral renal ischemia; RI‐DCN, unilateral renal ischemia followed by delayed contralateral nephrectomy; RK, right kidney.

FIGURE 7. Dot plots of log‐transformed renal tissular gene transcript levels by group and kidney. Data from the control, RI, and RI‐DCN group are plotted as blue circles, green squares, and magenta triangles, respectively. ACE, angiotensin‐converting enzyme; AGT, angiotensinogen; AT1R, angiotensin type‐1 receptor; IK, ischemic kidney; NIK, non‐ischemic kidney; REN, renin; RI, unilateral renal ischemia; RI‐DCN, unilateral renal ischemia followed by delayed contralateral nephrectomy; RK, right kidney.

FIGURE 8. Scatterplots of log‐transformed equilibrium concentrations of angiotensin I, II, or III in serum versus renal tissue, with lines of best fit and 95% confidence intervals (shaded areas) displayed. Correlation coefficient (R) and p‐values were calculated using Pearson's correlation analysis. Data from the control, RI, and RI‐DCN group are plotted as blue circles, green squares, and magenta triangles, respectively. Ang, angiotensin; RI‐DCN, unilateral renal ischemia followed by delayed contralateral nephrectomy; RI, unilateral renal ischemia.

FIGURE 9. Scatterplots of circulating and intrarenal renin‐angiotensin(‐aldosterone) system parameters versus serum creatinine concentration. Lines of best fit and 95% confidence intervals (shaded areas) are displayed. R and p‐values were calculated using Pearson's correlation analysis. Data from the control, RI, and RI‐DCN group are plotted as blue circles, green squares, and red triangles, respectively. ACE, angiotensin‐converting enzyme; AGT, angiotensinogen.

FIGURE 10. Scatterplots of circulating and intrarenal renin‐angiotensin‐aldosterone system parameters versus intrarenal angiotensin II concentrations. Lines of best fit and 95% confidence intervals (shaded areas) are displayed. Correlation coefficient (R) and p‐values were calculated using Pearson's correlation analysis. Data from the control, RI, and RI‐DCN group are plotted as blue circles, green squares, and magenta triangles, respectively. Ang, angiotensin; PRA, plasma renin activity.