The effect of propranolol on the serotonin concentration in the portal plasma after vagal nerve stimulation in the cat.
Efferent cervical vagal nerve stimulation in the cat caused a marked increase of the portal plasma 5-HT concentration. This increase was more than two-fold within 15 min of stimulation. After cessation of stimulation portal plasma 5-HT returned to basal levels within 10 min. Treatment with the beta-adrenoceptor antagonist propranolol, in various doses (0.1-2 mg/kg b.wt.), did not abolish but significantly reduced the response to vagal stimulation, particularly during the final part of the stimulation period. The results confirm the existence of a beta-adrenoceptor-mediated release of 5-HT, but also suggest that other mechanisms for 5-HT release may be involved in the response on vagal nerve stimulation.
D000319:Adrenergic beta-Antagonists; D000818:Animals; D002415:Cats; D004525:Efferent Pathways / Q000502:physiology; D004558:Electric Stimulation; D005260:Female; D008297:Male; D011433:Propranolol / Q000494:pharmacology*; D012701:Serotonin / Q000097:blood* / Q000378:metabolism; D013997:Time Factors; D014630:Vagus Nerve / Q000502:physiology*
D000319:Adrenergic beta-Antagonists; D012701:Serotonin; D011433:Propranolol