Activation of hypothalamic β-endorphin pools by reward induced by highly palatable food

doi:10.1016/0091-3057(83)90467-7

Pharmacology Biochemistry and Behavior

Volume 18, Issue 3, March 1983, Pages 443-447

https://doi.org/10.1016/0091-3057(83)90467-7 Get rights and content

Abstract

Experiments were performed to find biochemical evidence of an activation of endogenous opiate peptides in the brain by incentive reward. A method used to estimate specific in vivo opiate binding in rats using the labelled opiate agonist, ³H-etorphine, indicated a considerable reduction in opiate binding exclusively in the hypothalamus of non-deprived animals given a highly palatable food to eat for 20 min. Radioimmunoassay of the hypothalamus of rats under similar conditions found a pronounced drop in the concentration of β-endorphin, but not in dynorphin, in the hypothalamus, indicating a release and breakdown of β-endorphin. Therefore, the reduction in opiate binding in the hypothalamus may at least be partially explained by an occupation of opiate receptors by β-endorphin, causing a reduced availability of receptors to etorphine. A possible role of hypothalamic β-endorphin in the facilitation of reward pathways in the brain is discussed.

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Activation of hypothalamic β-endorphin pools by reward induced by highly palatable food

Abstract

Brain Res

Brain Res

Neurosci Lett

Physiol Behav

Eur J Pharmacol

Pharmacol Biochem Behav

Brain Res

Peptides

Peptides

Neuropharmacology

Neurosci Lett