Pharmacological activity of the new calcium antagonist, lacidipine, on isolated preparations.
1. The calcium-channel blocking activity of lacidipine has been studied compared with that of nifedipine and verapamil on the isolated rabbit heart and aorta. 2. All the compounds induced a dose-dependent negative inotropic effect (10(-8)-10(-5) M); although lacidipine showed less, but longer lasting, activity. 3. Lacidipine showed a weak negative chronotropic effect and nifedipine was ineffective. Only verapamil strongly decreased the heart rate. 4. The three calcium antagonists abolished vasopressin-induced coronary spasm and inhibited partially metoxamine-induced coronary spasm. Only lacidipine reduced basal coronary pressure. 5. In the aortic strips, all the compounds antagonized KCl-induced contractions, and they exerted a partial effect on noradrenaline- and angiotensin II-induced contractions.
Raddino
R
R
Cattedra di Cardiologia, Universitá Degli Studi di Brescia, P. le Spedali Civili 1, Italy.
Metra
M
M
Nodari
S
S
Pelá
G
G
Fappani
A
A
Dei Cas
L
L
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D003326:Coronary Circulation / Q000187:drug effects; D004095:Dihydropyridines / Q000494:pharmacology*; D005260:Female; D006321:Heart / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D009200:Myocardial Contraction / Q000187:drug effects; D009543:Nifedipine / Q000494:pharmacology; D011817:Rabbits; D017725:Ventricular Pressure / Q000187:drug effects; D014700:Verapamil / Q000494:pharmacology
D002121:Calcium Channel Blockers; D004095:Dihydropyridines; C060285:lacidipine; D014700:Verapamil; D009543:Nifedipine