Neonatal proinflammatory stress alters the expression of genes of corticosteroid receptors in the rat hippocampus: Septo-temporal differences

We studied the postponed effect of neonatal proinflammatory stress (NPS) on the expression of the glucocorticoid receptor (GR) and the mineralcorticoid receptor (MR) in the dorsal (DH) and ventral hippocampus (VH) of female and male rats. We found that in male Wistar rats the expression of GR mRNA is higher in the DH than in the VH. Induction of NPS by administration of bacterial lipopolysaccharide (LPS) during the neonatal period differentially influenced the expression of GR mRNA in the DH and VH of 30-day-old animals. In males, LPS administration in the neonatal age increased GR expression in the VH and did not influence in the DH whereas, in females, it increased expression in the DH and did not influence in the VH. The expression of MR was not altered by NPS. Thus, NPS induces long-term changes in different parts of the hippocampus, which is considered as one of the key brain structures involved in the pathogeny of depressive disorder.