Noradrenaline inhibits central serotonin release through alpha 2-adrenoceptors located on serotonergic nerve terminals

Naunyn Schmiedebergs Arch Pharmacol. 1982 Sep;320(3):272-4. doi: 10.1007/BF00510140.


The effect of noradrenaline on the depolarization-evoked release of 3H-5-hydroxytryptamine was investigated in superfused synaptosomes prepared from rat cortex and hippocampus and prelabelled with the radioactive indoleamine. Noradrenaline reduced in a concentration-dependent way the release of 3H-5-hydroxytryptamine elicited by 15 mM KCl. The inhibition was counteracted by the alpha-adrenoceptor antagonists phentolamine or yohimbine, but not by prazosin. The results indicate that, in rat brain, the inhibition of 5-hydroxytryptamine release by noradrenaline is mediated by adrenoceptors of the alpha 2-type localized on the terminal serotonergic fibres.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / drug effects
  • Brain / metabolism*
  • In Vitro Techniques
  • Male
  • Nerve Endings / metabolism
  • Norepinephrine / metabolism
  • Norepinephrine / pharmacology*
  • Rats
  • Rats, Inbred Strains
  • Receptors, Adrenergic / metabolism*
  • Receptors, Adrenergic, alpha / metabolism*
  • Serotonin / metabolism*
  • Synaptosomes / metabolism


  • Receptors, Adrenergic
  • Receptors, Adrenergic, alpha
  • Serotonin
  • Norepinephrine