Sex-specific restoration of MK-801-induced sensorimotor gating deficit by environmental enrichment.

Despite ample evidence of N-methyl-D-aspartate (NMDA) receptor dysfunction in schizophrenia, no study has addressed the effects of enriched environment (EE) on sensorimotor gating deficits induced by postnatal NMDA receptor blockade. We evaluated the effect of EE on sensorimotor gating (measured by prepulse inhibition, PPI), or on sensorimotor gating deficit induced by the NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801) in both sexes of Wistar rats. Rats were injected with MK-801 (1 mg/kg) on postnatal days (P) 6-10. EE was provided from birth up to the time of experiments on P28-30 or P58-60. PPI data were collected at three prepulse intensities and then averaged to yield global PPI. MK-801 treatment reduced PPI significantly in both sexes. While EE per se had no significant effect on PPI, it restored MK-801-induced PPI deficit only in male rats. An extended period of EE did not influence PPI deficit in female rats. Our results indicate that postnatal exposure to MK-801 may exert long-lasting effects on neuronal circuits underlying sensorimotor gating. Sex-specific modulation of such effects by EE suggests sexually dimorphic mechanisms are involved.

Validation of the Edinburgh Postnatal Depression Scale in an Iranian sample.

BACKGROUND: Considering the adverse effects of postpartum depression on both mother and infant, a screening instrument for early diagnosis seems to be of importance. AIMS: To assess the psychometric properties of the Persian version of Edinburgh Postnatal Depression Scale (EPDS) on a sample of Iranian postpartum women. METHOD: The EPDS was translated and back-translated in the standard method. The questionnaire was completed by 600 postpartum women. Hundred cases with an EPDS score of > or =9 and 100 cases with an EPDS of <9 were randomly selected for interview. Sensitivity, specificity, positive likelihood ratio, and receiver operating characteristics were calculated by comparing the EPDS sum score against the DSM-IV diagnoses. The correlation coefficient of the EPDS score with GHQ-12 score was calculated. Principal component analysis and internal consistency were assessed. RESULTS: The best cutoff scores for major depression were 12/13 with a sensitivity and specificity of 95.3% and 87.9%, respectively. The correlation coefficient of the total score of the Persian version of EPDS with the GHQ-12 total score was 0.76 (P < 0.001). A two-factor solution was selected as the most appropriate model based on both values and the score plot. The coefficient alpha for the whole scale was 0.83. CONCLUSION: The Persian version of EPDS is a reliable and valid measure for detecting postpartum depression. Furthermore, it seems acceptable to patients and a valid screening instrument for depression in postpartum women.