Affordable Access

Publisher Website

Interaction between noradrenergic and serotonergic brain systems as evidenced by behavioral and biochemical effects of microinjections of adrenergic agonists and antagonists into the median raphe nucleus

Authors
Journal
Pharmacology Biochemistry and Behavior
0091-3057
Publisher
Elsevier
Publication Date
Volume
19
Issue
1
Identifiers
DOI: 10.1016/0091-3057(83)90306-4
Keywords
  • Adrenergic Agents
  • Serotonergic Median Raphe Nucleus
  • Microinjection Study

Abstract

Abstract The effects of microinjections of adrenergic receptors agonists and antagonists into the median raphe nucleus (MR) on behavior and serotonin (5HT) metabolism was examined in rats. Administration of adrenergic alpha 1 and alpha 2 receptor agonists (noradrenaline, phenylephrine, clonidine) produced behavioral excitation in the open field test and a tendency to decrease the forebrain 5-hydroxyindolo-acetic acid (5HIAA) concentration. Opposite effects were seen after microinjection of adrenergic alpha receptor antagonists (phenoxybenzamine, phentolamine but not yohimbine). A significant negative correlation was found between the effects on locomotor activity and 5HIAA levels in these rats. No effect was present after injection of beta receptor agonist salbutamol or antagonist propranolol. It is suggested that noradrenaline released from noradrenergic terminals in the MR tonically inhibits the activity of 5HT neurons thus producing symptoms of 5HT deficiency and that this action of noradrenaline is probably limited to the effects on alpha 1 but not alpha 2 nor beta adrenoceptors in this brain region.

There are no comments yet on this publication. Be the first to share your thoughts.