HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 289/5/E814    most recent 00093.2005v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (7) Citing Articles via Google Scholar Google Scholar Articles by Koutkia, P. Articles by Grinspoon, S. Search for Related Content PubMed PubMed Citation Articles by Koutkia, P. Articles by Grinspoon, S.

Reciprocal changes in endogenous ghrelin and growth hormone during fasting in healthy women

¹Program in Nutritional Metabolism and Neuroendocrine Unit, Massachusetts General Hospital, Harvard Medical School; and ²Massachusetts General Hospital/Massachusetts Institute of Technology General Clinical Research Center Core Laboratory and ³Biostatistics Program, Boston, Massachusetts

Submitted 2 March 2005 ; accepted in final form 15 June 2005

Ghrelin stimulates growth hormone (GH) secretion, but it is unknown whether there is a feedback of GH on ghrelin secretion. In this study, we characterized the relatedness of GH and ghrelin in a model of acute caloric deprivation in 10 healthy women (age 26.7 ± 1.6 yr) during a 4-day fast in the early follicular phase. GH, ghrelin, and cortisol were assessed every hour over 24 h during an isocaloric diet and after a 4-day complete fast. Sampling during a normal diet at baseline demonstrated that ghrelin decreased 17.9% within 1 h after meals (P < 0.0001), but there was no meal effect on GH. BMI (22.3 ± 0.4 vs. 21.5 ± 0.4 kg/m², P < 0.0001) and IGF-I (312 ± 28 vs.124 ± 22 ng/ml, P < 0.0001) decreased during fasting. Mean 24-h GH increased (2.6 ± 0.5 vs. 5.6 ± 0.5 ng/ml, P < 0.001), but ghrelin decreased (441.3 ± 59.7 vs. 359.8 ± 54.2 pg/ml, P = 0.012). The peak ghrelin level decreased from 483.5 to 375.6 pg/ml (P < 0.0001), and the time of the peak ghrelin changed from 0415 to 1715. In contrast, the diurnal pattern of GH was maintained, with increases in the nadir (1.1 to 3.4 ng/ml) and peak GH concentrations (4.1 to 7.9 ng/ml) from the fed to fasted state (P < 0.0001). The change in morning GH concentrations was inversely related to the change in ghrelin (r = –0.79, P = 0.012). During complete short-term caloric deprivation in healthy women, ghrelin decreases, even as GH rises, and these processes appear to be reciprocal, suggesting that GH exhibits feedback inhibition on ghrelin. Our data provide new evidence of the physiological relationship of GH and ghrelin in response to changes in protein-energy metabolism.

nutrition; hunger; neuroendocrine; appetite

This article has been cited by other articles:

				J. M. Frecka and R. D. Mattes Possible entrainment of ghrelin to habitual meal patterns in humans Am J Physiol Gastrointest Liver Physiol, March 1, 2008; 294(3): G699 - G707. [Abstract] [Full Text] [PDF]

				N. A. Tritos and E. G. Kokkotou The Physiology and Potential Clinical Applications of Ghrelin, a Novel Peptide Hormone Mayo Clin. Proc., May 1, 2006; 81(5): 653 - 660. [Abstract] [Full Text] [PDF]