Effects of serotonergic 5-HT1A and 5-HT1B ligands on ventral pallidal neuronal activity.
To clarify the role of the 5-HT system in limbic outputs, the present study compared the effects of the 5-HT1A agonist 8-OH-DPAT and the 5-HT1B agonist CP-94253 with the non-selective 5-HT agonist TFMPP on the firing rate of ventral pallidal (VP) neurons recorded in chloral hydrate-anesthetized rats. 8-OH-DPAT (0.25-256 microg/kg i.v.) dose-dependently enhanced (9/26 neurons) or suppressed (8/26) activity, and the 5-HT1A antagonist (+)WAY-100135 often attenuated these responses. TFMPP (0.011-1.453 mg/kg i.v.) dose-dependently reduced the firing rate of 7/8 VP neurons tested. In contrast, CP-94253 (0.013-12.8 mg/kg i.v.) had little or no effect. In sum, these data suggest that the 5-HT1A receptor appears to be particularly important in influencing limbic outputs mediated via the VP.
Heidenreich
B A
BA
Department of Pharmacology and Experimental Therapeutics, Loyola University Chicago, Stritch School of Medicine, Maywood, IL 60153, USA.
Napier
T C
TC
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects* / Q000502:physiology; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005917:Globus Pallidus / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D008297:Male; D009474:Neurons / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D010879:Piperazines / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D044302:Receptor, Serotonin, 5-HT1B; D011985:Receptors, Serotonin / Q000187:drug effects* / Q000378:metabolism; D044263:Receptors, Serotonin, 5-HT1; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*
C097067:CP 94253; D010879:Piperazines; D011725:Pyridines; D044302:Receptor, Serotonin, 5-HT1B; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; C081293:WAY 100135; C018406:1-(3-trifluoromethylphenyl)piperazine; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin