Food intake and serum insulin responses to intraventricular infusions of insulin and IGF-I

doi:10.1016/0031-9384(91)90012-D

Physiology & Behavior

Volume 50, Issue 4, October 1991, Pages 745-749

https://doi.org/10.1016/0031-9384(91)90012-D Get rights and content

Abstract

Previous studies reported that intracerebroventricular (ICV) infusion of insulin decreased food intake in rats and baboons. Insulin can bind to insulin-like growth factor I (IGF-I) receptors and mimic the response of IGF-I. Our objective was to determine the effects of ICV infused-insulin or IGR-I on food intake in sheep. In the present study, a 6-day ICV infusion of insulin (123 ng/kg of body weight/day) but not of IGF-I (123 ng/kg of body weight/day) decreased food intake by 40% ( $p<0.003$ ) and body weight ( $p<0.015$ ) compared with control sheep. In addition, sheep that received ICV insulin or IGF-I had only half the concentration of insulin in serum as compared with controls. Our results support the hypothesis that ICV insulin does not decrease food intake through IGF-I receptors. Nevertheless, apparently both insulin and IGF-I in the brain can influence the concentration of insulin in blood.

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ArticleFood intake and serum insulin responses to intraventricular infusions of insulin and IGF-I

Abstract

Brain Res. Bull.

Livest. Prod. Sci.

J. Dairy Sci.

Dom. Anim. Endocrinol.

Brain Res.

J. Nutr.

Neuroscience

Appetite

Physiol. Behav.

Peptides

Metabolism

Physiol. Behav.

Physiol. Behav.

Physiol. Behav.

Am. J. Clin. Nutr.

Intracerebroventricular infusions of 3-OHB and insulin in a rat model of dietary obesity

Am. J. Physiol.

Regional concentrations of insulin in the rat brain

Endocrinology

Quantitative aspects of propionate metabolism and gluconeogenesis in sheep

Am. J. Physiol.

Potassium exchange between cerebrospinal fluid, plasma, and brain

Am. J. Physiol.

The effect of day length and level of feeding on serum prolactin in growing lambs

J. Endocrinol.

Article
Food intake and serum insulin responses to intraventricular infusions of insulin and IGF-I