The International Journal of Neuropsychopharmacology

Research Article

Cognitive impairments from developmental exposure to serotonergic drugs: citalopram and MDMA

Tori L. Schaefera1, Curtis E. Gracea1, Amanda A. Brauna1, Robyn M. Amos-Kroohsa1, Devon L. Grahama1, Matthew R. Skeltona1, Michael T. Williamsa1 and Charles V. Vorheesa1 c1

a1 Division of Child Neurology, Department of Pediatrics, Cincinnati Children's Research Foundation and University of Cincinnati College of Medicine, Cincinnati, OH, USA

Abstract

We previously showed that developmental 3,4-methylenedioxymethamphetamine (MDMA) treatment induces long-term spatial and egocentric learning and memory deficits and serotonin (5-HT) reductions. During brain development, 5-HT is a neurotrophic factor influencing neurogenesis, synaptogenesis, migration, and target field organization. MDMA (10 mg/kg × 4/d at 2 h intervals) given on post-natal day (PD) 11–20 in rats (a period of limbic system development that approximates human third trimester brain development) induces 50% reductions in 5-HT during treatment and 20% reductions when assessed as adults. To determine whether the 5-HT reduction is responsible for the cognitive deficits, we used citalopram (Cit) pretreatment to inhibit the effects of MDMA on 5-HT reuptake in a companion study. Cit attenuated MDMA-induced 5-HT reductions by 50% (Schaefer et al., 2012). Here we tested whether Cit (5 or 7.5 mg/kg × 2/d) pretreatment attenuates the cognitive effects of MDMA. Within each litter, different offspring were treated on PD11–20 with saline (Sal) + MDMA, Cit + MDMA, Cit + Sal or Sal + Sal. Neither spatial nor egocentric learning/memory was improved by Cit pretreatment. Unexpectedly, Cit + Sal (at both doses) produced spatial and egocentric learning deficits as severe as those caused by Sal + MDMA. These are the first data showing cognitive deficits resulting from developmental exposure to a selective serotonin reuptake inhibitor. These data indicate the need for further research on the long-term safety of antidepressants during pregnancy.

(Received September 14 2012)

(Reviewed October 17 2012)

(Revised October 29 2012)

(Accepted November 07 2012)

(Online publication January 11 2013)

Key words

  • Citalopram;
  • cognition;
  • development;
  • MDMA;
  • serotonin

Correspondence

c1 Address for correspondence: Dr C. V. Vorhees, Division of Child Neurology (MLC 7044), Cincinnati Children's Research Foundation, 3333 Burnet Ave., Cincinnati, OH 45229-3039, USA. Tel.: (513) 636 8622 Fax: (513) 636 3912 Email: charles.vorhees@cchmc.org