Pharmacological aspects of calcium antagonism. Short term and long term benefits.

Calcium antagonists are widely used in the management of a variety of cardiovascular disorders, including angina pectoris, myocardial infarction, atherosclerosis and hypertension. At the cellular level these drugs act primarily by limiting calcium ion (Ca++) entry through voltage-sensitive, Ca(++)-selective channels. This effect contributes to the antiatherogenic properties of calcium antagonists and is primarily responsible for their ability to reduce systolic and diastolic blood pressure, and to protect the myocardium. The cardioprotective effect of calcium antagonists is a complex phenomenon that needs to be considered in terms of the immediate consequences of Ca(++)-channel blockade and subsequent reduction in cytosolic Ca++, together with the long term benefits. These long term benefits include protection of the vasculature, an attenuation of hypertension-induced hypertrophy and improved left ventricular diastolic function. However, irrespective of whether it is the short or long term effects of calcium antagonists that are being considered, it is their ability to lower cytosolic Ca++ that is primarily responsible for their cardio- and vascular-protective effects.