Distribution of 5-HT1B and 5-HT1D receptors in the inner ear

Migraine and anxiety disorders are frequently co-morbid with balance disorders This study examined the relative distribution of subtypes of serotonin (5-HT) receptor in the inner ear of monkeys and rats Most vestibular ganglion cells were immunoreactive for 5-HT1B and 5-HT1D receptors in macaques and rats In the inner ear, 5-HT1B and 5-HT1D receptor immunopositivity was associated with endothelial cells of the vestibular ganglion, spiral ganglion, vestibulocochlear nerve, spiral ligament and stria vascularis It was noteworthy that 5-HT1B and 5-HT1D receptors are expressed in parallel sites in peripheral vestibular and trigeminal systems, which may be a factor underlying the efficacy of triptans in treating migraine and migrainous vertigo Because the vestibular ganglion and trigeminal ganglion are both within the subarachnoid space, an interaction between 5-HT1B and TRPV1 receptors on blood vessel and ganglion cells may also contribute to the vasospasm and the comorbid headache, dizziness, nausea and vomiting that accompany subarachnoid hemorrhage (C) 2010 Elsevier B V All rights reserved