Quantitative Study The Variation On Number Of Neurons In The Hippocampus Of Rat With Disorders Of Cortical Development By Stereological Methods

Objective：To investigate the variation of number and volume of hippocampus neuron inCA1,CA3and DG region of rats with disorder of cortical developments(DCDs) inducedby X-ray using stereological method, Exploring the pathophysiological mechanismbetween DCDs formation and refractory epilepsy, and provide the theory basis forprevention and control IE.Methods：Choose5normal rats and model rats with2months old respectively, take out thebrain and embedding it with paraffin blocks, and then serial coronal sections inthickness of8μm were cut. The sections were uniformly and randomly sampled fromthe consecutive sections through hippocampus according to the principles ofsystematic，uniform and random sampling．The sections were stained for Nisslsubstance for the quantification of neuron number in CA1，CA3,DG region and volumeof hippocampus using stereological device.Results：The number of unilateral hippocampus neuron in CA1，and DG region in normalrats is8.35×10~4±1.44×10~4、8.23×10~4±1.60×10~4and14.3×10~4±2.24×10~4respectively，and correspondingly3.70×10~4±1.96×10~4、3.57×10~4±1.47×10~4and6.86×10~4±4.85×10~4in cortical dysplasia model rats. The volume of unilateral hippocampus in normal ratsand disorders of cortical development rats is14.18±1.52mm3and8.49±3.41mm3.Compare to normal rats, the number of neuron in CA1,CA3and DGregion and volume of hippocampus in model rats is decreased(P <0.05). Conclusion：Comparing with normal rats, the number and volume of hippocampus neuron inCA1, CA3and DG region of rats with cortical dysplasia induced by X-ray issignificantly decreased, which indicate the possible that DCDs is the microscopicpathology foundation structure of epilepsy or/and IE formation.