title: Inhibitory effect of betahistine on polysynaptic neurons in the lateral vestibular nucleus.
abstract: Effects of betahistine, an antivertigo drug, were examined on the lateral vestibular nucleus (LVN) neurons of cats anesthetized with alpha-chloralose. Spike generation of monosynaptic LVN neurons elicited by vestibular nerve stimulation remained unaffected with intravenous administration of betahistine up to 5 mg/kg and with iontophoretic application of the drug up to 200 nA. In contrast, the spike generation of polysynaptic I neurons in the LVN was dose-dependently inhibited by intravenous as well as iontophoretic application of betahistine. These results suggest that small doses of betahistine more selectively interfere with synaptic transmission in the polysynaptic I neurons than in the monosynaptic neurons.
mesh_terms: D000818:Animals; D001621:Betahistine / Q000494:pharmacology*; D002415:Cats; D004305:Dose-Response Relationship, Drug; D005071:Evoked Potentials / Q000187:drug effects; D007275:Injections, Intravenous; D009433:Neural Inhibition / Q000187:drug effects*; D009474:Neurons / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology*; D013569:Synapses / Q000187:drug effects*; D014725:Vestibular Nerve / Q000187:drug effects; D014726:Vestibular Nuclei / Q000187:drug effects*
chemical_list: D011725:Pyridines; D001621:Betahistine