Coinjections of NPY(1-36) or [Leu31,Pro34]NPY with adrenaline in the nucleus tractus solitarius of the rat counteract the vasodepressor responses to adrenaline

Neurosci Lett. 1994 Apr 25;171(1-2):27-31. doi: 10.1016/0304-3940(94)90596-7.

Abstract

The cardiovascular effects of adrenaline microinjected alone or together with neuropeptide Y (NPY) receptor agonists into the nucleus tractus solitarius (Sol) of the anaesthetized rat have been investigated in order to evaluate NPY/adrenergic receptor interactions. In the dose range 0.05-20 nmol, adrenaline microinjected unilaterally into the Sol produced significant dose-related reductions in mean arterial blood pressure and heart rate. The vasodepressor action of a close to ED50 dose of adrenaline (0.5 nmol) was significantly counteracted by a threshold dose of NPY (1-36) (1 pmol) and of the NPY Y1 receptor agonist [Leu31,Pro34]NPY (2.5 pmol) microinjected into the Sol, but not by a threshold dose of NPY(13-36)(50 fmol), a selective Y2 receptor agonist. The present study provides evidence for an antagonistic NPY Y1/adrenergic receptor interaction in the Sol of the rat, involved in cardiovascular regulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Pressure / drug effects
  • Epinephrine / antagonists & inhibitors*
  • Epinephrine / pharmacology
  • Heart Rate / drug effects
  • Hemodynamics / drug effects*
  • Male
  • Microinjections
  • Neuropeptide Y / analogs & derivatives*
  • Neuropeptide Y / pharmacology*
  • Peptide Fragments / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Neuropeptide Y / antagonists & inhibitors
  • Solitary Nucleus / physiology*

Substances

  • Neuropeptide Y
  • Peptide Fragments
  • Receptors, Neuropeptide Y
  • neuropeptide Y (13-36)
  • neuropeptide Y, Leu(31)-Pro(34)-
  • Epinephrine