Fig. 2

Surgery in mice impairs cognitive function and hippocampal morphology as a model of PNDs. Adult male C57BL/6J mice were subjected to exploratory laparotomy (termed “Surgery”). Control mice did not undergo surgery. All mice were subjected to 4 days of training in the Barnes maze beginning 7 days after the surgery; memory phase testing was performed on days 11 and 18 post-surgery. a Time to find the target hole during the training sessions and b latency in identifying the target hole after training were measured. Fear conditioning tests were performed on days 19 and 20 after surgery. Freezing times were quantified c in context and d in response to a cue (n = 8 per group). e Micrographs of hippocampal sections stained with hematoxylin and eosin (n = 4 per group). Magnification, × 20 for regions CA1, CA3, and DG in hippocampus. *P < 0.05 vs. control