Effects of N-terminal fragments of beta-endorphin on feeding in chicks.
It is known that N-terminal fragments of beta-endorphin have biological activities, such as an antagonism effect of beta-endorphin (1-31) on the secretion of hormones or thermoregulation in mammals. We studied the effects of the N-terminal fragments on feeding behavior in male broiler chicks. Intracerebroventricular administration of beta-endorphin (1-27) (0.4nmol) stimulated feeding behavior compared with saline control during the 60-min experimental period. beta-Endorphin (1-17) (2.0nmol) also increased food intake at 30min postinjection. Co-injection of either beta-endorphin (1-27) or (1-17) was effective in reducing full-length beta-endorphin-induced feeding in chicks. These data suggest that the N-terminal fragments of beta-endorphin act as a partial agonist, and may regulate the activity of the central opioidergic system in chicks.
Yanagita
Kouichi
K
Laboratory of Animal Behavior and Physiology, Graduate School of Biosphere Science, Hiroshima University, 1-4-4 Kagamiyama, Higashi-Hiroshima 739-8528, Japan.
Shiraishi
Jun-Ichi
J
Fujita
Masanori
M
Bungo
Takashi
T
D000818:Animals; D000831:Animals, Newborn; D001522:Behavior, Animal / Q000187:drug effects; D002645:Chickens; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D004435:Eating / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects*; D007276:Injections, Intraventricular / Q000379:methods; D008297:Male; D018377:Neurotransmitter Agents / Q000494:pharmacology*; D010446:Peptide Fragments / Q000494:pharmacology; D013997:Time Factors; D001615:beta-Endorphin / Q000737:chemistry / Q000494:pharmacology*
D004338:Drug Combinations; D018377:Neurotransmitter Agents; D010446:Peptide Fragments; D001615:beta-Endorphin