Oxytocin is a precursor of potent behaviourally active neuropeptides

Eur J Pharmacol. 1983 Oct 14;94(1-2):125-31. doi: 10.1016/0014-2999(83)90449-1.


An oxytocin fragment which accumulated during the incubation of oxytocin with brain synaptic membranes was chemically characterized as the hexapeptide pGlu-Asn-Cys(Cys)-Pro-Leu-Gly-NH2 [( pGlu4, Cyt6]OXT-(4-9]. This peptide was approximately a hundred times more potent than oxytocin in attenuating memory consolidation as tested in a passive avoidance test situation; the dose-response relationship was bell-shaped. The des-glycinamide derivative [pGlu4, Cyt6]OXT-(4-8) was nearly as active, but showed a linear dose-response relationship. The data indicate that oxytoxin can act as precursor for potent behaviourally active neuropeptides.

MeSH terms

  • Animals
  • Avoidance Learning / physiology
  • Behavior, Animal / physiology*
  • Female
  • In Vitro Techniques
  • Injections, Intraventricular
  • Male
  • Membranes / metabolism
  • Nerve Tissue Proteins / metabolism
  • Nerve Tissue Proteins / physiology*
  • Oxytocin / metabolism*
  • Protein Precursors / metabolism
  • Rats
  • Uterine Contraction / drug effects


  • Nerve Tissue Proteins
  • Protein Precursors
  • Oxytocin