Infusion of the serotonin1B (5-HT1B) agonist CP-93,129 into the parabrachial nucleus potently and selectively reduces food intake in rats.
Unilateral infusion of the selective 5-HT1B agonist, CP-93,129 (3-(1,2,5,6-tetrahydropyrid-4-yl) pyrrolo[3,2-b]pyrid-5-one) into the parabrachial nucleus (PBN) of the pons reduced food consumption by rats. The hypophagia was dose-related (ED50 approximately 1 nmol) and associated with fewer observations of feeding and more periods of inactivity. Water intake, grooming and exploratory activity were unaffected. CP-93,129 also decreased food intake when injected into the hypothalamic paraventricular nucleus, but this action was 50-fold less potent than administration into the PBN. Autoradiography demonstrated 5-HT1B sites in the PBN; this binding was displaced by CP-93,129. The results implicate parabrachial 5-HT1B receptors in mediating serotonergic enhancement of satiation.
Lee
M D
MD
Department of Pharmacology, MCP-Hahnemann School of Medicine, Allegheny University of the Health Sciences, Philadelphia, PA 19129, USA.
Aloyo
V J
VJ
Fluharty
S J
SJ
Simansky
K J
KJ
D000818:Animals; D001345:Autoradiography; D003864:Depression, Chemical; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects*; D007267:Injections; D008297:Male; D011149:Pons / Q000033:anatomy & histology / Q000502:physiology*; D011725:Pyridines / Q000008:administration & dosage / Q000494:pharmacology*; D011758:Pyrroles / Q000008:administration & dosage / Q000494:pharmacology*; D011869:Radioligand Assay; D051381:Rats; D017207:Rats, Sprague-Dawley; D011985:Receptors, Serotonin / Q000378:metabolism; D012528:Satiety Response / Q000187:drug effects; D017366:Serotonin Receptor Agonists / Q000008:administration & dosage / Q000494:pharmacology*
D011725:Pyridines; D011758:Pyrroles; D011985:Receptors, Serotonin; D017366:Serotonin Receptor Agonists; C065046:3-(1,2,5,6-tetrahydropyrid-4-yl)pyrrolo(3,2-b)pyrid-5-one