title: Plasma ghrelin levels in lean and obese humans and the effect of glucose on ghrelin secretion.
abstract: Ghrelin, a novel GH-releasing peptide isolated from human and rat stomach, stimulates food intake and GH secretion. We determined plasma ghrelin concentrations in patients with simple obesity, anorexia nervosa, and type 2 diabetes mellitus by RIA. We also studied plasma ghrelin responses to glucose load and meal intake and obtained a 24-h profile of circulating ghrelin in humans. Plasma ghrelin concentrations in patients with simple obesity and anorexia nervosa were lower and higher, respectively, than those of healthy subjects with normal body weight. Among those with type 2 diabetes mellitus, obese patients had lower and lean patients higher fasting plasma ghrelin concentrations than normal-weight patients. Fasting plasma ghrelin concentration was negatively correlated with body mass index in both nondiabetic and diabetic patients. Plasma ghrelin concentrations of normal subjects decreased significantly after oral and iv glucose administration; a similar response was also observed in diabetic patients after a meal tolerance test, reaching a nadir of 69% of the basal level after the meal. Circulating plasma ghrelin showed a diurnal pattern with preprandial increases, postprandial decreases, and a maximum peak at 0200 h. This study demonstrates that nutritional state is a determinant of plasma ghrelin in humans. Ghrelin secretion is up-regulated under conditions of negative energy balance and down-regulated in the setting of positive energy balance. These findings suggest the involvement of ghrelin in the regulation of feeding behavior and energy homeostasis.
authors.affiliation: Department of Internal Medicine, Miyazaki Medical College, Miyazaki 889-1692, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Shiiya
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Nakazato
authors.forename: Masanari
authors.initials: M
authors.lastname: Mizuta
authors.forename: Yukari
authors.initials: Y
authors.lastname: Date
authors.forename: Muhtashan S
authors.initials: MS
authors.lastname: Mondal
authors.forename: Muneki
authors.initials: M
authors.lastname: Tanaka
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Nozoe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hosoda
authors.forename: Kenji
authors.initials: K
authors.lastname: Kangawa
authors.forename: Shigeru
authors.initials: S
authors.lastname: Matsukura
mesh_terms: D000328:Adult; D000856:Anorexia Nervosa / Q000097:blood; D002940:Circadian Rhythm; D003924:Diabetes Mellitus, Type 2 / Q000097:blood; D005260:Female; D054439:Ghrelin; D005947:Glucose / Q000494:pharmacology*; D005951:Glucose Tolerance Test; D006801:Humans; D008297:Male; D009765:Obesity / Q000097:blood*; D036361:Peptide Hormones; D010455:Peptides / Q000097:blood / Q000378:metabolism*; D019518:Postprandial Period; D013270:Stomach / Q000187:drug effects
chemical_list: D054439:Ghrelin; D036361:Peptide Hormones; D010455:Peptides; D005947:Glucose