Urocortin in the lateral septal area modulates feeding induced by orexin A in the lateral hypothalamus.
The intermediate portion of the lateral septum (LSi) contains high levels of urocortin (UCN) peptide and type 2 corticotropin-releasing hormone (CRH) receptor (CRHR2) and has anatomic and functional connections with the lateral hypothalamus (LH). We tested the effect of UCN in the LSi on feeding. Injection of 10 or 30 pmol UCN into LSi significantly decreased feeding in food-deprived rats for 24 h without producing conditioned taste aversion (CTA). Pretreatment with a CRH receptor antagonist, alpha-helical CRH (alpha-hCRH), blocked the inhibitory effect of UCN on deprivation-induced feeding at 1 and 2 h postinjection. Furthermore, UCN in the LSi significantly decreased feeding induced by LH-injected orexin A at 2 and 4 h postinjection, and addition of alpha-hCRH blocked the inhibitory effect of UCN on orexin A-induced feeding. In conclusion, UCN significantly inhibits feeding induced by deprivation and LH-injected orexin A without producing a CTA, an effect that is mediated by CRHR2. These data define the LSi as an important site for UCN-induced anorexia and indicate that LSi UCN may influence orexin A feeding signals in the LH.
Wang
Chuanfeng
C
Veterans Affairs Medical Center, Geriatric, Research, Education and Clinical Center and Research Service, Minneapolis 55417, USA.
Kotz
Catherine M
CM
D000818:Animals; D001069:Appetite Regulation / Q000187:drug effects / Q000502:physiology; D001522:Behavior, Animal / Q000187:drug effects; D002352:Carrier Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D002755:Choice Behavior / Q000187:drug effects; D003346:Corticotropin-Releasing Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D005247:Feeding Behavior / Q000187:drug effects*; D005508:Food Deprivation / Q000502:physiology; D007031:Hypothalamus / Q000187:drug effects* / Q000502:physiology; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D008845:Microinjections; D009479:Neuropeptides / Q000008:administration & dosage / Q000494:pharmacology*; D064446:Orexin Receptors; D000068797:Orexins; D051381:Rats; D017207:Rats, Sprague-Dawley; D018019:Receptors, Corticotropin-Releasing Hormone / Q000037:antagonists & inhibitors; D043562:Receptors, G-Protein-Coupled; D018013:Receptors, Neuropeptide; D012439:Saccharin / Q000494:pharmacology; D020665:Septum of Brain / Q000187:drug effects* / Q000502:physiology; D013649:Taste / Q000502:physiology; D054832:Urocortins
C101531:CRF receptor type 2; D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D064446:Orexin Receptors; D000068797:Orexins; D018019:Receptors, Corticotropin-Releasing Hormone; D043562:Receptors, G-Protein-Coupled; D018013:Receptors, Neuropeptide; D054832:Urocortins; C069206:alpha helical corticotropin-releasing hormone; D003346:Corticotropin-Releasing Hormone; D012439:Saccharin