title: Dorsal facial area of cat medulla; 5-HT2 action on glutamate release in regulating common carotid blood flow.
abstract: Serotonin (5-HT) may inhibit glutamate release in the dorsal facial area (DFA) of the medulla and decrease common carotid arterial (CCA) blood flow. We attempted to clarify which subtype(s) of 5-HT receptor was involved. A microdialysis probe was inserted in DFA. The concentration of glutamate in dialysates were determined by chromatography. Glutamate concentration was dose-dependently decreased by perfusion of 5-HT or DOI, a 5-HT2 agonist, but not by 5-CT, a 5-HT1 agonist. The 5-HT-induced decrease in glutamate was reversed by co-perfusion of ketanserin, a 5-HT2 antagonist, but not by propranolol, a 5-HT1 antagonist. CCA blood flow was decreased when 5-HT or DOI was perfused, and was reversed by co-perfusing ketanserin. In conclusion, 5-HT may inhibit glutamate release via 5-HT2 receptor in DFA, resulting in the reduction of CCA blood flow.
authors.affiliation: Department of Education and Research and Geriatric Medical Center, Taichung Veterans General Hospital, Taiwan, ROC. jskuo@vghtc.vghtc.gov.tw
authors.forename: J S
authors.initials: JS
authors.lastname: Kuo
authors.forename: H T
authors.initials: HT
authors.lastname: Li
authors.forename: N N
authors.initials: NN
authors.lastname: Lin
authors.forename: C S
authors.initials: CS
authors.lastname: Yang
authors.forename: F C
authors.initials: FC
authors.lastname: Cheng
mesh_terms: D000818:Animals; D017536:Carotid Artery, Common / Q000187:drug effects*; D002415:Cats; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism*; D008297:Male; D008526:Medulla Oblongata / Q000187:drug effects* / Q000378:metabolism; D017551:Microdialysis; D012701:Serotonin / Q000494:pharmacology*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology
chemical_list: D017366:Serotonin Receptor Agonists; D012701:Serotonin; D018698:Glutamic Acid