Autoradiographic localization of 5-HT1 receptors to human and canine basilar arteries.

Autoradiographic techniques were used to identify serotonergic binding sites in human and canine basilar artery segments. 5-HT1, but not 5-HT2, receptors could be localized to the medial layer of the vascular wall using both [3H]LSD and [3H]5-HT. The identification of 5-HT1 binding sites in human and canine basilar arteries provides anatomical evidence that the 5-HT1 receptor mediates vasoconstriction in these major intracranial vessels.