alpha-Adrenoceptors and Acute Migraine Therapy

In contrast to the well-established role of serotonin (5-hydroxytryptamine; 5-HT) 5-HT(1B) receptors in mediating constriction within the carotid vascular bed of dogs and pigs, the role of alpha-adrenoceptors and their subtypes has not been as well understood. Using experimental animal models and alpha(1)-adrenoceptor and alpha(2)-adrenoceptor agonists (phenylephrine and BHT-933, respectively) and antagonists (prazosin and rauwolscine, respectively), it was recently shown that activation of either receptor produces a cranioselective vasoconstriction. Subsequently, investigations employing relatively selective antagonists at alpha(1)- (alpha(1A), alpha(1B), alpha(1D)) and alpha(2)- (alpha(2A), alpha(2B), alpha(2C)) adrenoceptor subtypes revealed that specific receptors mediate carotid vasoconstrictor responses. Since alpha(1B)-adrenoceptors and alpha(2C)-adrenoceptors do not seem to play an important role in the cardiovascular regulation, it is suggested that selective agonists at these receptors may provide a promising novel avenue for the development of acute antimigraine drugs. (c) 2002 Prous Science. All rights reserved.