Differential effects of Tyr-MIF-1, MIF-1, and naloxone on peptide YY-induced hyperphagia

Academic Article


  • Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH2) and MIF-1 (Pro-Leu-Gly-NH2) act as opiate antagonists in various behavioral systems including ingestion. Central injection of peptide YY (PYY) elicits a powerful feeding response in satiated rats, and the opioid antagonist naloxone decreases eating in a variety of conditions including PYY-stimulated eating. Therefore, the aim of this study was to examine the effects of Tyr-MIF-1 and MIF-1 as opiate antagonists on a naloxone-sensitive PYY model of hyperphagia. Naloxone at doses of 1.0 and 10.0 mg/kg, SC, decreased hyperphagia induced by 2.4 μg PYY injected in the PVN. MIF-1 and Tyr-MIF-1 had no effect on PYY-induced eating at doses comparable to naloxone (0.1 to 10.0 mg/kg, IP). These results suggest that in this model of eating behavior, Tyr-MIF-1 and MIF-1 do not act as opiate antagonists. © 1994.
  • Authors

    Published In

  • Peptides  Journal
  • Digital Object Identifier (doi)

    Author List

  • Hagan MM; Moss DE
  • Start Page

  • 243
  • End Page

  • 245
  • Volume

  • 15