5-HT1B antagonists modulate clearance of extracellular serotonin in rat hippocampus.
In vivo chronoamperometry was used to determine the effects of locally applied antagonists of the serotonin-1B (5-HT1B) receptor (cyanopindolol, 5-HT-moduline and methiothepin) on the clearance of 5-HT in the CA3 region of the dorsal hippocampus and the corpus callosum (a brain region devoid of serotonin transporters and 5-HT1B receptors) of the rat. When 5-HT was pressure ejected into these regions, reproducible signals were detected. In the CA3 region, local application of 5-HT1B antagonists decreased the rate of clearance of the serotonin signal comparably to the selective 5-HT uptake inhibitor (SSRI), fluvoxamine. By contrast, in the corpus callosum, none of the drugs altered the 5-HT signal. One interpretation of these data is that 5-HT1B receptors can modulate the activity of the 5-HT transporter.
Daws
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LC
Department of Pharmacology, University of Texas Health Science Center at San Antonio, 78284-7764, USA. daws@uthscsa.edu
Gerhardt
G A
GA
Frazer
A
A
D000704:Analysis of Variance; D000818:Animals; D003337:Corpus Callosum / Q000187:drug effects / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D008657:Metabolic Clearance Rate; D008719:Methiothepin / Q000494:pharmacology; D009479:Neuropeptides / Q000494:pharmacology; D009842:Oligopeptides / Q000494:pharmacology; D010869:Pindolol / Q000031:analogs & derivatives / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000494:pharmacology*
C102005:5-HT-moduline; D009479:Neuropeptides; D009842:Oligopeptides; D012702:Serotonin Antagonists; D012701:Serotonin; C047975:cyanopindolol; D008719:Methiothepin; D010869:Pindolol