Expression of neurogranin in hippocampus of rat offspring exposed to restraint stress and pulsed magnetic fields.

Stressor acting upon the organism during pregnancy can produce distinct and long lasting effects on the offspring. However, the essential mechanism remains unclear. Neurogranin (Ng) is a postsynaptic brain-specific protein involved in the regulation of calcium signaling and neuronal plasticity. Our purpose was to investigate whether Ng plays a regulating role in the effects of prenatal restraint stress (PS) and prenatal pulsed magnetic fields (PMFs) on the hippocampus of rat offspring. Sprague Dawley female rats at gestational days 14-20 were given restraint stress or pulsed magnetic fields. The male and female offspring rats were sacrificed at the age of 1 month. The expression of Ng in the offspring hippocampus was determined using immunohistochemistry and western blotting. The results showed that PS induces a significantly inhibitory effect on the expression of Ng, especially in female offspring. The 0.11 T of prenatal PMFs could increase the expression of Ng in offspring hippocampus. There was no significant difference between female and male offspring in PMFs group. The prenatal restraint stress-induced decrease in Ng expression in offspring hippocampus might be associated with the deficit in spatial learning and memory reported previously. The 0.11 T of prenatal PMFs induced a significant stimulatory effect on protein expression of Ng. It was believed that PMFs stress might enhance the synaptic growth and remodeling.