Role of the Hypothalamic Arcuate Nucleus in Regulation of Food Intake (Review Study)

Introduction Arcuate nucleus (ARC) is an aggregation of neurons in the basal hypothalamus, is thought to play a pivotal role in the integration of signals regulating food intake. Given the important role of hypothalamus in regulating of food intake, the aim of this review study was discussion on the mediating role of the ARC in feeding behaviour. Materials and Methods In 2016, in this study by searching related articles published in valid scientific databases such as PubMed, Web of Science, Scopus, Elsevier, Springer, Science Direct, and SID with standard keywords and reference. Lists of identified articles were reviewed for the additional articles during 1998 to 2016. Results These studies reported that the arcuate nucleus includes several populations of neurons that contain neuropeptide Y, agouti-related peptide, GABA, and αMSH. These neurons, in the most ventromedial part of the nucleus, project strongly to the other nuclei of hypothalamus, and are important in the regulation of feeding behaviour and increasing or decreasing of food intake. The ARC is available to peripheral signals of energy balance, via median eminence, because this part of the brain is not protected completely by the blood brain barrier. Conclusion Based on the literature, the ARC is the part of brain where some neurotransmitters exert the most potent orexigenic or anorexigenic effects in mammals and birds. Food intake is inhibited by leptin, insulin, αMSH, and serotonin and activated by NP Y, Agrp, NO F/Q, and GABA. However, a few neurotransmitter such as ghrelin has a dual function, ghrelin stimulates feeding in mammals, although it attenuates food intake in birds