Fourth ventricular injection of CART peptide inhibits short-term sucrose intake in rats.
Expression of CART (cocaine-amphetamine-regulated transcript) in the rat hypothalamus is modulated by nutritional status, and injection of synthetic CART peptide into the forebrain ventricular system suppresses food intake, indicating a possible role in hypothalamic control of energy homeostasis. Its recent identification in cell bodies and central terminals of vagal afferent neurons additionally suggests a role in brainstem mechanisms of meal termination and satiety. We demonstrate here that CART[55-102] (0.2 nmol) suppresses short-term sucrose intake and overnight chow intake in non-food-deprived rats even more when delivered into the fourth ventricle as compared to the lateral ventricle. At the threshold dose (0.02-0.08 nmol) no readily noticeable motor impairments were observed. The results are consistent, but do not prove a site of action within the brainstem, possibly in mediating vagal satiety signals at the level of the NTS.
Zheng
H
H
Neurobiology of Nutrition Laboratory, Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA 70808, USA.
Patterson
C
C
Berthoud
H R
HR
D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D001933:Brain Stem / Q000187:drug effects / Q000502:physiology; D019422:Dietary Sucrose / Q000494:pharmacology*; D004435:Eating / Q000187:drug effects*; D020546:Fourth Ventricle; D007276:Injections, Intraventricular; D008297:Male; D009419:Nerve Tissue Proteins / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012527:Satiation / Q000187:drug effects; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein
D019422:Dietary Sucrose; D009419:Nerve Tissue Proteins; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein