Effect of Neonatal Hypoxia on Leptin, Insulin, Growth Hormone and Body Composition in the Rat

H. Raff; E. D. Bruder; B. M. Jankowski; R. J. Colman

doi:10.1055/s-2001-14929

Hormone and Metabolic Research, Table of Contents

Horm Metab Res 2001; 33(3): 151-155
DOI: 10.1055/s-2001-14929

Original Clinical

Effect of Neonatal Hypoxia on Leptin, Insulin, Growth Hormone and Body Composition in the Rat

H. Raff^{1, 2} , E. D. Bruder¹ , B. M. Jankowski¹ , R. J. Colman³

¹ Endocrine Research Laboratory, St. Luke’s Medical Center, Milwaukee, WI, USA
² Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA
³ Wisconsin Regional Primate Research Center, University of Wisconsin, Madison, WI, USA

Abstract

The purpose of the present study was to evaluate the effect of exposure to hypoxia from birth to 7 days of age on leptin, insulin, growth hormone (GH), insulin-like growth factor-1 (IGF-1), glucose, corticosterone, body weight, and body composition in rats studied at 7 days of age and then after return to normoxia. Hypoxia for the first 7 days of life resulted in a significant decrease in plasma leptin, body weight, and an increase in corticosterone and insulin with no change in plasma glucose, GH or IGF-1. There was no significant effect of hypoxia on % lean body mass, but a small but significant increase in % body fat. Bone mineral density (BMD) was lower in 7-day-old hypoxic rats as compared to normoxic controls. All hormonal variables and BMD had normalized by 7 days after return to normoxia. However, body weight remained lower even 5 weeks after return to normoxia. We conclude that leptin is decreased during neonatal hypoxia despite no change in adiposity. Furthermore, insulin is increased probably to overcome the effects of increased counterregulatory hormones (such as corticosterone).

Key words:

Corticosterone - Body Weight - Newborn - Bone Mineral Density - Anoxia - Insulin-Like Growth Factor 1

Full Text

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H. Raff, Ph.D.

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