SBP (a), urinary protein excretion (b) and urinary protein excretion/creatinine ratio (c). All treatments decreased SBP to levels comparable with that of WKY. SHR/ND showed substantial proteinuria compared with WKY or SHR. Compared with amlodipine, cilnidipine greatly suppressed the progression of proteinuria in SHR/ND. *P < 0.05, **P < 0.01 vs. WKY, #P < 0.05 vs. SHR/ND, †P < 0.05 vs. SHR/ND + amlodipine at 34 weeks old (n = 11–12). SHR, spontaneously hypertensive rat; WKY, Wistar–Kyoto rats.