S-adenosyl-L-methionine prevents 5-HT(1A) receptors up-regulation induced by acute imipramine in the frontal cortex of the rat

Neurosci Lett. 2002 Mar 15;321(1-2):110-4. doi: 10.1016/s0304-3940(02)00044-7.

Abstract

S-adenosyl-L-methionine (SAM) has shown efficacy in speeding the onset of the antidepressant effect of imipramine in depressed patients. This effect may be related to their interactions at the serotonin(1A) (5-HT(1A)) receptors. Acute imipramine up-regulated the frontal cortex 5-HT(1A) receptors (B(max), 51.5 +/- 8.4 fmol/mg protein) vs. saline (B(max), 27.5 +/- 5.9 fmol/mg protein), and did not show antidepressant effect. Acute SAM and imipramine+SAM did not modify frontal cortex 5-HT(1A) receptors, and showed antidepressant effects (decrease of the immobility response of 26%, P<0.01; and 47%, P<0.001) vs. saline. All the chronic treatments showed antidepressant effects and up-regulated the hippocampus 5-HT(1A) receptors. SAM prevents the 5-HT(1A) receptor up-regulation induced by acute imipramine in the frontal cortex. This mechanism may contribute to imipramine's antidepressant effect.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antidepressive Agents, Tricyclic / agonists*
  • Depression / drug therapy*
  • Depression / metabolism
  • Depression / physiopathology
  • Drug Interactions / physiology
  • Frontal Lobe / drug effects*
  • Frontal Lobe / metabolism
  • Frontal Lobe / physiopathology
  • Imipramine / agonists*
  • Male
  • Motor Activity / drug effects
  • Motor Activity / physiology
  • Neural Inhibition / drug effects
  • Neural Inhibition / physiology
  • Neurons / drug effects*
  • Neurons / metabolism
  • Raphe Nuclei / drug effects
  • Raphe Nuclei / metabolism
  • Raphe Nuclei / physiopathology
  • Rats
  • Rats, Wistar
  • Receptors, Serotonin / drug effects*
  • Receptors, Serotonin / metabolism
  • Receptors, Serotonin, 5-HT1
  • S-Adenosylmethionine / pharmacology*
  • Serotonin / metabolism
  • Stress, Psychological / drug therapy
  • Stress, Psychological / etiology
  • Stress, Psychological / physiopathology
  • Synaptic Transmission / drug effects
  • Synaptic Transmission / physiology
  • Up-Regulation / drug effects*
  • Up-Regulation / physiology

Substances

  • Antidepressive Agents, Tricyclic
  • Receptors, Serotonin
  • Receptors, Serotonin, 5-HT1
  • Serotonin
  • S-Adenosylmethionine
  • Imipramine