Modulation of the action of calcium antagonists in arteries.
This paper is a review of the experimental evidence showing that specific binding sites for dihydropyridine Ca antagonists are involved in inhibition of stimulus-dependent Ca entry into arterial cells and thereby in inhibition of the contractile response. The apparent affinity of the dihydropyridine binding site is related to the proportion of a high- and a low-affinity state which is regulated by membrane potential but could also be dependent upon other factors such as G proteins. Among Ca antagonists, a subgroup of agents exhibiting voltage dependence may be identified. Their apparent pharmacological potency is highly dependent on resting membrane potential and on the duration of the depolarizing stimulus.
Godfraind
T
T
Laboratoire de Pharmacodynamie Générale et de Pharmacologie, Université Catholique de Louvain, Bruxelles, Belgique.
Morel
N
N
Wibo
M
M
D000818:Animals; D001158:Arteries / Q000187:drug effects*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015220:Calcium Channels / Q000187:drug effects; D006973:Hypertension / Q000188:drug therapy; D008564:Membrane Potentials; D009119:Muscle Contraction; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000502:physiology
D002121:Calcium Channel Blockers; D015220:Calcium Channels