d(CH2)5Tyr(Me)-[Orn8]vasotocin, a potent oxytocin antagonist, antagonizes penile erection and yawning induced by oxytocin and apomorphine, but not by ACTH-(1-24)

Eur J Pharmacol. 1987 Feb 10;134(2):221-4. doi: 10.1016/0014-2999(87)90168-3.

Abstract

Intraventricular (i.c.v.) injection of d(CH2)5-Tyr(Me)-[Orn8]vasotocin, a potent oxytocin antagonist, antagonized in a dose-dependent manner (10-100 ng) penile erection and yawning induced by the systemic injection of apomorphine (80 micrograms/kg s.c.) or by the i.c.v. injection of oxytocin (30 ng). In contrast, the oxytocin antagonist, even at the dose of 10 micrograms, did not modify penile erection and yawning induced by the i.c.v. injection of ACTH-(1-24). These results suggest that apomorphine, but not ACTH-(1-24), induce penile erection and yawning by releasing oxytocin in some brain area.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenocorticotropic Hormone / pharmacology*
  • Animals
  • Apomorphine / administration & dosage
  • Apomorphine / pharmacology*
  • Cosyntropin / pharmacology*
  • Injections, Intraventricular
  • Injections, Subcutaneous
  • Male
  • Oxytocin / administration & dosage
  • Oxytocin / analogs & derivatives
  • Oxytocin / antagonists & inhibitors*
  • Oxytocin / pharmacology
  • Penile Erection / drug effects*
  • Rats
  • Rats, Inbred Strains
  • Vasotocin / analogs & derivatives*
  • Vasotocin / pharmacology
  • Yawning / drug effects*

Substances

  • Cosyntropin
  • Oxytocin
  • oxytocin,1-(beta-mercapto-(beta, beta-cyclopentamethylene)propionic acid)-Tyr(OMe)(2)-Orn(8)-
  • Adrenocorticotropic Hormone
  • Apomorphine
  • Vasotocin