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.
KEYWORDS: Hippocampus, Neurogranin, Offspring, Prenatal restraint stress, Pulsed magnetic fields