Feeding behavior and gene expression of appetite-related neuropeptides in mice lacking for neuropeptide Y Y5 receptor subclass.
Neuropeptide Y (NPY) is a potent neurotransmitter for feeding. Besides NPY, orexigenic neuropeptides such as agouti-related protein (AgRP), and anorexigenic neuropeptides such as alpha-melatonin stimulating hormone (MSH) and cocaine-amphetamine-regulated transcript (CART) are also involved in central feeding regulation. During fasting, NPY and AgRP gene expressions are up-regulated and POMC and CART gene expressions are down-regulated in hypothalamus. Based on the network of peptidergic neurons, the former are involved in positive feeding regulation, and the latter are involved in negative feeding, which exert these feeding-regulated peptides especially in paraventricular nucleus (PVN). To clarify the compensatory mechanism of knock-out of NPY system on feeding, change in gene expressions of appetite-related neuropeptides and the feeding behavior was studied in NPY Y5-KO mice. Food intake was increased in Y5-KO mice. Fasting increased the amounts of food and water intake in the KO mice more profoundly. These data indicated the compensatory phenomenon of feeding behavior in Y5-KO mice. RT-PCR and ISH suggested that the compensation of feeding is due to change in gene expressions of AgRP, CART and POMC in hypothalamus. Thus, these findings indicated that the compensatory mechanism involves change in POMC/CART gene expression in arcuate nucleus (ARC). The POMC/CART gene expression is important for central compensatory regulation in feeding behavior.
Higuchi
Hiroshi
H
Division of Pharmacology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Chuo-ku, Niigata 951-8510, Japan. hhiguchi@med.niigata-u.ac.jp
Niki
Takeshi
T
Shiiya
Tomohiro
T
D000222:Adaptation, Physiological; D054369:Agouti-Related Protein / Q000378:metabolism; D000818:Animals; D001069:Appetite Regulation / Q000235:genetics*; D001835:Body Weight; D004326:Drinking; D004435:Eating; D005215:Fasting; D005247:Feeding Behavior; D005260:Female; D005786:Gene Expression Regulation; D007028:Hypothalamic Hormones / Q000378:metabolism; D007031:Hypothalamus / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D008297:Male; D008543:Melanins / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009478:Neuropeptide Y / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism; D000068797:Orexins; D010907:Pituitary Hormones / Q000378:metabolism; D011333:Pro-Opiomelanocortin / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D017476:Receptors, Neuropeptide Y / Q000172:deficiency* / Q000235:genetics; D013997:Time Factors; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein
D054369:Agouti-Related Protein; C515199:Agrp protein, mouse; D007028:Hypothalamic Hormones; D047908:Intracellular Signaling Peptides and Proteins; D008543:Melanins; D009419:Nerve Tissue Proteins; D009478:Neuropeptide Y; D009479:Neuropeptides; D000068797:Orexins; D010907:Pituitary Hormones; D012333:RNA, Messenger; D017476:Receptors, Neuropeptide Y; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein; C100568:neuropeptide Y5 receptor; D011333:Pro-Opiomelanocortin; C019463:melanin-concentrating hormone