Effect of intrahypothalamic injection of [D-Ala2,D-Leu5]enkephalin on feeding and temperature in the rat

Eur J Pharmacol. 1983 Dec 23;96(3-4):243-9. doi: 10.1016/0014-2999(83)90313-8.


The effectiveness of the delta-opioid agonist [D-Ala2,D-Leu5]enkephalin (DADLE) in eliciting alterations in feeding and core temperature in rats was compared to morphine. When injected into the ventromedial hypothalamus this peptide caused a dose-related increase in feeding which was rapid in onset and of short duration, and a short-lived increase in temperature. Neither of these effects was blocked by the intrahypothalamic injection of naloxone. The alpha-adrenoreceptor antagonist phentolamine significantly reduced DADLE-stimulated feeding, although it did not counteract the hyperthermia. Since the delta-opioid agonist DADLE is more potent than the mu-agonist, morphine, and produces its effect more rapidly, the delta-opiate receptor may have an influence on the regulation of feeding.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Body Temperature / drug effects*
  • Dose-Response Relationship, Drug
  • Enkephalin, Leucine / administration & dosage
  • Enkephalin, Leucine / analogs & derivatives*
  • Enkephalin, Leucine-2-Alanine
  • Feeding Behavior / drug effects*
  • Hypothalamus / drug effects
  • Injections, Intraventricular
  • Male
  • Morphine / administration & dosage
  • Naloxone / administration & dosage
  • Phentolamine
  • Rats
  • Rats, Inbred Strains


  • Naloxone
  • Enkephalin, Leucine
  • Enkephalin, Leucine-2-Alanine
  • Morphine
  • Phentolamine