Author/Editor		Budihna, MV
Title		Farmakologija kalcijevih antagonistov
Translated title		The pharmacology of calcium antagonists
Type		članek
Source		Med Razgl
Vol. and No.		Letnik 32, št. 1
Publication year		1993
Volume		str. 65-86
Language		slo
Abstract		Calcium antagonists constitute a chemically and pharmacologically diverse group of drugs. Chemically, at least four major types of calcium antagonists can be distinguished; they include phenylalkylamines, dihydropyridines, benzothiazepines and piperazines. As a group they share the common property of slowing the transmembrane entry of calcium ions through either voltagčactivated, or (probably) receptor operated, ion selective channels. They differ from one another also in terms of their tissue specificity and selectivity. Different types (L, T, N) of calcium channels have been identified and their distribution in different tissues is specific. The molecular properties and the differential binding characteristics of the subgroups of calcium antagonists have been defined. At least one of calcium antagonists, diltiazem, has an intracellular action. All calcium antagonists share the ability to dilate blood vessels, but there is a marked difference in potency and selectivity, even within individual subgroups. The dihydropyridines are relatively selective antagonists of vascular smooth muscle cell calcium uptake. Their ability to inhibit myogenic vascular tone contributes to their predominant in vivo effect on vascular beds characterized by a relatively high myogenic tone, such as the coronary and skeletal muscle beds. Additional mechanisms contributing to the antihypertensive action of dihydropyridines include interference with neural control of circulation, as well as intrarenal actions to promote electrolyte and water excretion. In myocardium, the tissue protecting effects efffects od calcium antagonists, especially the dihydropyridine-based group, in the presence of hypertension involve not only reduction of hypertrophy, but they also reduce ischemia-induced injury and the incidence of damage due to lipid peroxidation.(trunc.)
Descriptors		CALCIUM CHANNELS CALCIUM CHANNEL BLOCKERS ARTERIES KIDNEY HEART