Cilnidipine, the N- and L-type calcium channel antagonist, reduced on 24-h urinary catecholamines and C-peptide in hypertensive non-insulin-dependent diabetes mellitus.

To evaluate the effects of cilnidipine (CNP), L- and N-type calcium channel blocker and nilvadipine (NVP) on 24-h urinary epinephrine (U-EP), norepinephrine (U-NE), dopamine (U-DA) and C-peptide (U-CPR) in patients associated with hypertension and non-insulin-dependent diabetes mellitus (HT-NIDDM), a randomized crossover study was performed with 35 HT-NIDDM patients. The patients were given CNP (10 mg/day) and NVP (8 mg/day), separately, for 4 weeks each. After CNP treatment, U-NE, U-DA and U-CPR levels were significantly reduced compared with pre-treatment levels: 160.4 +/- 12.7 to 111.7 +/- 8.9 microg/day (mean +/- S.E., P < 0.005); 934.8 +/- 163.4 to 590.3 +/- 33.4 microg/day (P < 0.05); 86.7 +/- 9.9 to 57.6 +/- 7.4 microg/day (P < 0.05), respectively. Although no significant differences were observed in U-EP, U-NE, U-DA and U-CPR levels by NVP treatment, U-NE, U-DA and U-CPR levels after CNP treatment were significantly lower than those after NVP treatment: 111.7 +/- 8.9 versus 155.0 +/- 13.7 microg/day (P < 0.02); 590.3 + 33.4 versus 822.2 +/- 104.3 microg/day (P < 0.05); 57.6 +/- 7.4 versus 80.6 +/- 8.1 microg/day (P < 0.05), respectively. In conclusion, it was demonstrated that CNP treatment significantly reduced U-NE, U-DA and U-CPR excretion compared with NVP treatment in HT-NIDDM patients.