title: Chronic central administration of Ghrelin increases bone mass through a mechanism independent of appetite regulation.
abstract: Leptin plays a critical role in the central regulation of bone mass. Ghrelin counteracts leptin. In this study, we investigated the effect of chronic intracerebroventricular administration of ghrelin on bone mass in Sprague-Dawley rats (1.5 μg/day for 21 days). Rats were divided into control, ghrelin ad libitum-fed (ghrelin ad lib-fed), and ghrelin pair-fed groups. Ghrelin intracerebroventricular infusion significantly increased body weight in ghrelin ad lib-fed rats but not in ghrelin pair-fed rats, as compared with control rats. Chronic intracerebroventricular ghrelin infusion significantly increased bone mass in the ghrelin pair-fed group compared with control as indicated by increased bone volume percentage, trabecular thickness, trabecular number and volumetric bone mineral density in tibia trabecular bone. There was no significant difference in trabecular bone mass between the control group and the ghrelin ad-lib fed group. Chronic intracerebroventricular ghrelin infusion significantly increased the mineral apposition rate in the ghrelin pair-fed group as compared with control. In conclusion, chronic central administration of ghrelin increases bone mass through a mechanism that is independent of body weight, suggesting that ghrelin may have a bone anabolic effect through the central nervous system.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hyung Jin
authors.initials: HJ
authors.lastname: Choi
authors.forename: Kyoung Ho
authors.initials: KH
authors.lastname: Ki
authors.forename: Jae-Yeon
authors.initials: JY
authors.lastname: Yang
authors.forename: Bo Young
authors.initials: BY
authors.lastname: Jang
authors.forename: Jung Ah
authors.initials: JA
authors.lastname: Song
authors.forename: Wook-Young
authors.initials: WY
authors.lastname: Baek
authors.forename: Jung Hee
authors.initials: JH
authors.lastname: Kim
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: An
authors.forename: Sang Wan
authors.initials: SW
authors.lastname: Kim
authors.forename: Seong Yeon
authors.initials: SY
authors.lastname: Kim
authors.forename: Jung-Eun
authors.initials: JE
authors.lastname: Kim
authors.forename: Chan Soo
authors.initials: CS
authors.lastname: Shin
mesh_terms: D000818:Animals; D001066:Appetite / Q000502:physiology; D015519:Bone Density / Q000187:drug effects*; D001842:Bone and Bones / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000378:metabolism; D004334:Drug Administration Schedule; D004435:Eating / Q000187:drug effects; D054439:Ghrelin / Q000008:administration & dosage* / Q000097:blood; D007276:Injections, Intraventricular; D020738:Leptin / Q000097:blood; D008297:Male; D011859:Radiography; D051381:Rats; D017207:Rats, Sprague-Dawley; D015430:Weight Gain / Q000187:drug effects*
chemical_list: D054439:Ghrelin; D020738:Leptin