title: Increased production of active ghrelin is relevant to hyperphagia in nonobese spontaneously diabetic Torii rats.
abstract: An abnormal eating behavior is often associated with diabetes mellitus in individuals. In the present study, we investigated the mechanisms underlying the relationship among uncontrolled diabetes, food intake, and the production of ghrelin, an orexigenic hormone, in spontaneous diabetic Torii (SDT) rats. Male SDT rats and age-matched control Sprague-Dawley (SD) rats were housed from 8 to 38 weeks of age. Body weight and daily food intake were measured weekly, whereas blood and whole stomach samples were obtained at the age of 8, 25, and 38 weeks in both SDT and SD rats. The SDT rats at both 25 and 38 weeks of age demonstrated significantly lower body weights despite almost doubled food consumption compared with the SD rats of the same age. The SDT rats showed overt hyperglycemia at 25 and 38 weeks of age with concomitant hypoinsulinemia. The plasma active ghrelin levels and the ratio to total ghrelin levels of SDT rats at 38 weeks of age were significantly higher than those of SD rats of the same age. Stomach ghrelin and ghrelin O-acyltransferase messenger RNA expression levels were higher in SDT rats than in SD rats after the induction of diabetes, with a concomitant decrease of stomach ghrelin-immunopositive cell numbers in SDT rats at 38 weeks of age. The SDT rats with uncontrolled hyperglycemia show hyperphagia with a concomitant increase of plasma active ghrelin concentration. This report is the first to clarify the relevance of ghrelin to hyperphagia in diabetic state over an extended period.
authors: Institute of Animal Experimentation, Kurume University School of Medicine, Kurume 830-0011, Japan.
authors: Hiroharu
authors: H
authors: Mifune
authors: Yoshihiro
authors: Y
authors: Nishi
authors: Yuji
authors: Y
authors: Tajiri
authors: Taku
authors: T
authors: Masuyama
authors: Hiroshi
authors: H
authors: Hosoda
authors: Kenji
authors: K
authors: Kangawa
authors: Masayasu
authors: M
authors: Kojima
mesh_terms: D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism; D054439:Ghrelin / Q000096:biosynthesis* / Q000235:genetics; D006943:Hyperglycemia / Q000097:blood / Q000378:metabolism*; D006963:Hyperphagia / Q000097:blood / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018709:Statistics, Nonparametric
chemical_list: D054439:Ghrelin; D012333:RNA, Messenger; D000217:Acyltransferases; C534462:ghrelin O-acyltransferase, rat