THE TIMING OF PRENATAL IMMUNE CHALLENGE DETERMINES THE EXTENT OF WHITE MATTER MICROSTRUCTURAL ANOMALIES RELEVANT TO SCHIZOPHRENIA

Abstract

following transfer into the dark side they were conditioned by receiving light and tone paired with a mild unavoidable foot shock on three occasions. On return to the dark side of the chamber 24 and 48 h later the total time spent freezing was recorded to monitor learning and memory. Results: Isolated animals exhibited hyperactivity during the first 30 minutes of LMA compared with GH controls (477.7+130.6 vs 609.6+165.6 counts, respectively) but this just failed to reach statistical significance (p>0.05 by one-way ANOVA). AM630 had no significant effect on LMA. Saline injected GH rats successfully discriminated the novel object (p 0.05). GH controls froze significantly longer than SI rats irrespective of whether they had received AM630 or not both at 24 h and 48 h after the foot shock in the CER (p<0.01 by 2 way ANOVA repeated measures). Discussion: SI produced the expected hyperactivity in a novel arena and cognitive deficits in both novel object recognition and contextual fear conditioning, consistent with this being a valuable model of schizophrenia but none of these alterations were reversed by acute treatment with a CB2 receptor antagonist. CB2 receptors are possibly not involved in the long lasting behavioural defects produced by this neurodevelopmental modulation in rats.