[Calcium antagonists in the prophylactic treatment of migraine].

Calcium channel antagonists have been employed in the prophylactic treatment of migraine. Their major action is the inhibition of Ca2+ influx into smooth muscle cells that is mediated through high voltage-sensitive Ca2+ channels. These drugs had been introduced for the treatment of migraine mainly because of 2 of their effects were considered to be of potential benefit to these patients: their vasodilatory effect and their protective action against the harmful effects of hypoxia on cerebral issue. However, recent studies have provided evidence that in the central nervous system, they directly affect neuronal functions known to be calcium-dependent, such as neurotransmitter synthesis and release, inhibition of cortical spreading depression, and neuronal excitability. Although the exact mechanism of prophylactic effects calcium channel antagonists against migraine attacks remains unknown, alterations in Ca2+ channel function in the central nervous system are believed to play a key role in prophylaxis of migraine.