title: Chronic intracerebroventricular administration of relaxin-3 increases body weight in rats.
abstract: Bolus-administered intracerebroventricular (ICV) relaxin-3 has been reported to increase feeding. In this study, to examine the role of relaxin-3 signaling in energy homeostasis, we studied the effects of chronically administered ICV relaxin-3 on body weight gain and locomotor activity in rats. Two groups of animals received vehicle or relaxin-3 at 600 pmol/head/day, delivered with Alzet osmotic minipumps. In animals receiving relaxin-3, food consumption and weight gain were statistically significantly higher than those in the vehicle group during the 14-day infusion. During the light phase on days 2 and 7 and the dark phase on days 3 and 8, there was no difference in locomotor activity between the two groups. Plasma concentrations of leptin and insulin in rats chronically injected with relaxin-3 were significantly higher than in the vehicle-injected controls. These results indicate that relaxin-3 up-regulates food intake, leading to an increase of body weight and that relaxin-3 antagonists might be candidate antiobesity agents.
authors.affiliation: Laboratory of Seeds Finding Technology, Eisai Co., Ltd., Tsukuba, Ibaraki, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Hida
authors.forename: Eiki
authors.initials: E
authors.lastname: Takahashi
authors.forename: Kodo
authors.initials: K
authors.lastname: Shikata
authors.forename: Tomoko
authors.initials: T
authors.lastname: Hirohashi
authors.forename: Toru
authors.initials: T
authors.lastname: Sawai
authors.forename: Takashi
authors.initials: T
authors.lastname: Seiki
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Tanaka
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Kawai
authors.forename: Osamu
authors.initials: O
authors.lastname: Ito
authors.forename: Toru
authors.initials: T
authors.lastname: Arai
authors.forename: Akira
authors.initials: A
authors.lastname: Yokoi
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Hirakawa
authors.forename: Hiroo
authors.initials: H
authors.lastname: Ogura
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nagasu
authors.forename: Norimasa
authors.initials: N
authors.lastname: Miyamoto
authors.forename: Junro
authors.initials: J
authors.lastname: Kuromitsu
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects* / Q000502:physiology; D004435:Eating / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007276:Injections, Intraventricular; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000097:blood; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009419:Nerve Tissue Proteins / Q000037:antagonists & inhibitors / Q000502:physiology; D009765:Obesity / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000008:administration & dosage; D012065:Relaxin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D007328:Insulin; D020738:Leptin; D009419:Nerve Tissue Proteins; C480238:RLN3 protein, human; C466742:RLN3 protein, rat; D011994:Recombinant Proteins; D012065:Relaxin