The effects of prenatal stress on expression of p38 MAPK in offspring hippocampus

Abstract

The hippocampus, which has the highest density of GC receptors in the brain, is involved in the regulation of the HPA and the behavioral responses to stress. Overexposure to corticosteroid hormones is harmful to hippocampal neuron integrity. Our purpose is to investigate the effects of prenatal stress (PNS) on expression of p38 mitogen-activated protein kinase (p38 MAPK) in offspring hippocampal neurons using Western blotting and Immunohistochemistry. The prenatal restraint stress induces significant increase in the expression of p-p38 MAPK and total p38 MAPK in female offspring hippocampus. The level of p-p38 MAPK in PNS female offspring rats was significantly increased (126.41±3.937, n=6) compared with that in the control female offspring rats (101.35±3.468, n=6, P<0.01). Immunoblot analysis revealed there was significant difference in the level of total p38 MAPK between the female control and prenatal restraint stress offspring rats (101.70±3.162 vs. 128.111±2.724, respectively, P<0.01). Immunodensity of p38 MAPK was significantly increased above female control in PNS female offspring hippocampal CA3 and CA4 fields (P<0.001 vs. control group, CON). The data suggest that exposure of animals to a period of stressful experience during a critical phase could impose lasting effects on the offspring hippocampal neurons cellular signalling of offspring hippocampus.