Serotonin-induced contraction of canine basilar artery: mediation by 5-HT1 receptors.

Serotonin and related agonists cause a marked contraction of canine basilar artery segments. These contractions can be inhibited by a variety of serotonergic antagonists. Absolute potencies of both serotonin agonists and antagonists in chamber contraction studies significantly correlate (P less than 0.01) with their potencies for 5-HT1, but not 5-HT2, receptors as defined by central nervous system radioligand binding studies. Serotonin-induced contractions of canine basilar artery segments appear to be mediated by 5-HT1 receptors.