The influence of temperature upon depolarizing responses of rat isolated vagal nerve to 5-hydroxytryptamine.
In isolated cervical segments of rat vagus nerve, over the temperature range 5-45 degrees C, reversible depolarizations to 5-hydroxytryptamine (5-HT) were maximal at 10 degrees C and negligible at 45 degrees C. Dose-response curves for this depolarization were compared at 20 degrees C and 37 degrees C, with a similar sensitivity but marked proportionate reduction at 37 degrees C vs 20 degrees C, whilst the 5-HT-induced depression of vagal compound action potentials seen at 20 degrees C was abolished at 37 degrees C; such changes at 20 degrees C or 37 degrees C were insensitive to inhibitors of 5-HT-uptake (zimelidine) or MAO (pargyline). 5-HT may participate in presynaptic inhibition of C-fibre afferents.
D000200:Action Potentials; D000818:Animals; D066298:In Vitro Techniques; D008564:Membrane Potentials; D051381:Rats; D012701:Serotonin / Q000502:physiology*; D013696:Temperature; D014630:Vagus Nerve / Q000502:physiology*
D012701:Serotonin