sympathetic effects of diltiazem and Ro 40-5967 (a novel calcium channel blocker) ... Plasma noradrenaline level was increased more during diltiazem infusion ...
Br. J. Pharmacol. (1994), 113, 395-402
Q'I
Macmillan Press Ltd, 1994
Effects of the calcium channel blockers, diltiazem and Ro 40-5967, on systemic haemodynamics and plasma noradrenaline levels in conscious dogs with pacing-induced heart failure Jinbo Su, Nathalie Renaud, Alain Carayon, Bertrand Crozatier & 'Luc Hittinger, with the technical assistance of Monique Laplace I.N.S.E.R.M. U400, Faculte de Medecine, 94010 Creteil Cedex and from Laboratoire de Biochimie Medicale (A.C.), 91 Bld de L'Hopital, 75634 Paris Cedex 13, France 1 Calcium channel blockers increase cardiovascular morbidity and mortality in patients with left ventricular dysfunction. These adverse effects are probably related to the negative inotropic effect of calcium channel blockers and/or a neurohormonal activation. 2 The present study was designed to examine, in conscious dogs, the acute haemodynamic and sympathetic effects of diltiazem and Ro 40-5967 (a novel calcium channel blocker) in the control state and in heart failure. 3 Thirteen dogs were instrumented with a micromanometer and an aortic catheter. After completion of experiments in the control state, heart failure was induced by right ventricular pacing (250 beats min-', 3 weeks). Diltiazem and Ro 40-5967 were given intravenously (0.8 mg kg-' and 1.0 mg kg-' respectively). Cardiac output was measured by a thermodilution technique. 4 In the control state, both agents decreased similarly mean aortic pressure with significant increases in heart rate, cardiac output (both + 1.l0 min-' and P
