title: Synaptic relationships between proopiomelanocortin- and ghrelin-containing neurons in the rat arcuate nucleus.
abstract: Both proopiomelanocortin (POMC) and ghrelin peptides are implicated in the feeding regulation. The synaptic relationships between POMC- and ghrelin-containing neurons in the hypothalamic arcuate nucleus were studied using double-immunostaining methods at the light and electron microscope levels. Many POMC-like immunoreactive axon terminals were found to be apposed to ghrelin-like immunoreactive neurons and also to make synapses with ghrelin-like immunoreactive neuronal perikarya and dendritic processes. Most of the synapses were symmetrical in shape. A small number of synapses made by ghrelin-like immunoreactive axon terminals on POMC-like immunoreactive neurons were also identified. Both the POMC- and ghrelin-like immunoreactive neurons were found to contain large dense granular vesicles. These data suggest that the POMC-producing neurons are modulated via synaptic communication with ghrelin-containing neurons. Moreover, ghrelin-containing neurons may also have a feedback effect on POMC-containing neurons through direct synaptic contacts.
authors.affiliation: Department of Anatomy, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.
authors.forename: Jian-Lian
authors.initials: JL
authors.lastname: Guan
authors.forename: Hiromi
authors.initials: H
authors.lastname: Okuda
authors.forename: Fumiko
authors.initials: F
authors.lastname: Takenoya
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kintaka
authors.forename: Michiko
authors.initials: M
authors.lastname: Yagi
authors.forename: Lihua
authors.initials: L
authors.lastname: Wang
authors.forename: Mayumi
authors.initials: M
authors.lastname: Seki
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Hori
authors.forename: Haruaki
authors.initials: H
authors.lastname: Kageyama
authors.forename: Seiji
authors.initials: S
authors.lastname: Shioda
mesh_terms: D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000378:metabolism* / Q000648:ultrastructure; D054439:Ghrelin / Q000378:metabolism*; D008297:Male; D008854:Microscopy, Electron; D009474:Neurons / Q000378:metabolism* / Q000648:ultrastructure; D011333:Pro-Opiomelanocortin / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013569:Synapses / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D054439:Ghrelin; D011333:Pro-Opiomelanocortin