Intracerebroventricular administration of octopamine stimulates food intake of chicks through alpha(2)-adrenoceptor.
Octopamine, known to be an important neurotransmitter in invertebrates, has been noted to have several similarities to noradrenaline (NA) in mammals. The present study was done to elucidate whether central injection of octopamine enhances the feeding behavior of chicks and to investigate the interaction of octopamine with both alpha(1)- and alpha(2)-adrenoceptors. We found that the intracerebroventricular injection of octopamine significantly stimulated food intake of neonatal chicks during 30 min postinjection, but not thereafter. Moreover, this octopamine-induced eating response was attenuated by the alpha(2)-antagonist yohimbine, but not by the alpha(1)-antagonist prazosin. These results suggest that the action of octopamine on the feeding behavior of the neonatal chick is similar to that of NA, since octopamine regulates food intake through the alpha(2)-adrenoceptor.
Laboratory of Animal Science, Department of Agrobiological Science, Faculty of Agriculture, Ehime University, Matsuyama 790-8566, Japan. bungo@agr.ehime-u.ac.jp
Takashi
T
Bungo
Tamae
T
Higaki
Hiroshi
H
Ueda
Mitsuhiro
M
Furuse
D058647:Adrenergic alpha-2 Receptor Agonists; D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000317:Adrenergic alpha-Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D002645:Chickens / Q000502:physiology*; D004435:Eating / Q000187:drug effects*; D007276:Injections, Intraventricular; D008297:Male; D009655:Octopamine / Q000008:administration & dosage / Q000494:pharmacology*; D011224:Prazosin / Q000008:administration & dosage / Q000494:pharmacology; D013268:Stimulation, Chemical; D015016:Yohimbine / Q000008:administration & dosage / Q000494:pharmacology
D058647:Adrenergic alpha-2 Receptor Agonists; D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D009655:Octopamine; D015016:Yohimbine; D011224:Prazosin