The Correlation Along Nerve Growth Factor,the Repairing Of Neuron Damage And Mossy Fibers Sprouting In Rat Hippocampus After Lesion

Objective to explore the correlation along nerve growth factor,the repairing of neuron damage,mossy fibers sprouting (MFS)in rat hippocampus and the role of NGF in excitability synaptic reorganization circuit in temporal lobe epilepsy induced by kainic acid.Method Antisense or sense oligonucleotide to NGF and/or PBS buffer were injected into the ventricles of rats of temporal lobe epilepsy model induced by kainic acid(KA)and so as the control rats,then they were executed at 48h,72h,1w and 4w after lesion respectively.Immunohistochemical,pathobiology staining and Timm's silver sulfide staining were used to examine the effect of antisense oligonucleotide to NGF upon the neuron damage repairing and patho-change after lesion,synapse reconstitution and MFS in rat hippocampus of the KA model and did so for the control rats.Results the NGF-like protein marked increased at 48h after lesion,then the NGF-like protein expression's peak was at 72h and kept at a high level at least about 4w,with positive correlation to MFS.Timm's staining showed that multiple aberrant Timm's granules were found in the inner molecular layer(IML)of the dentate gyrus and stratum lucidum of CA3 area in the hippocampus of the KA model intracerebroventricularly injected with sense oligonucleotide to NGF and PBS,fewer aberrant Timm's granules were found in the hippocampus IML and stratum lucidum of the KA model rats intracerebroventricularly injected with antisense oligonucleotide to NGF.No NGF-like protein increased and aberrant Timm's granule were found in the hippocampal of non-KA model rats intracerebroventricular injected with antisense oligonucleotides to NGF.No obvious discrepancy of behavior between the epileptic rats injected antisense oligonucleotide and the sense oligonucleotide ones.Conclusions The protein of NGF marked increased with time-dependence after lesion,and coexisted with MFS.NGF may play an important role on neuron remodeling and promoting the MFS caused by repeated epileptic convulsion in the course of MF synaptic organization.The expression of NGF-like protein can be upregulated by intracerebroventricular injection of KA,but it wound be decreased by intracerebroventricular injection of antisense oligonucleotides to NGF.Inhibiting NGF-like protein may play a vital role on regulating neuron remodeling and inhibiting the MFS caused by repeated epileptic convulsion in the course of MF synaptic organization after intracerebroventricular injected with antisense oligonucleotides to NGF,but the definite relation between NGF and the development of epileptic should be further investigated.