Expression Of GAP-43in Hippocampus Of Kainic Acid Kindling Epileptic Rats And Its Relation With Learning And Memory

Objective Establishing epilepsy rat model by kainic acid light, dark avoidance test to observe the kainic acid kindling epileptic model rats in different time period of learning and memory function, detection of synaptophysin, growth associated protein-43(neuronal growth associated protein, GAP-43) lit in kainic acid expression in hippocampus of epileptic rats model, to investigate the relationship between GAP-43and learning and memory.Methods1. A correlation with learning and memory in the rat model of epilepsy kainic acid:the6-8week old healthy male SD rats, weight220-250g. The rats were randomly divided into Epilepsy Kindled group,sham operation group, normal control group, epilepsy group n=72, sham operation group n=24, control n=24. The rats were divided into Id,7d,30d,3sub groups, sham operation group only saline injection, operation, no injection of kainic acid, the blank control group and model group, sham operation group and the same feeding environment, each matching the relative number of normal rats as control. The behaviors of all rats were observed, with dark experimental latency record each rats method (LT) andshuttling back and forth times (EN), to study the learning and spatial memory function.2. The relationship between the expression of learning and memory in rat hippocampal GAP-43:rat single cage feeding, dark avoidance test, noexternal stimuli were killed painless kainic acid kindling epileptic model group, sham operation group and blank control group8rats, the remainingrats into the next sub group. Kainic acid kindling epileptic model groupevery subgroup dark avoidance test in1d,7d,30d at different time points in rats were killed painless, Relationship between expression of specimens by immunohistochemistry, RT-PCR and Western blot technology to study the kainic acid kindling, GAP-43mRNA and protein in hippocampus of epileptic model rats and discuss with learning and memory.Result1. Sprague-Dawley rat epilepsy model of learning and memory related research results kainic acid kindling:kainic acid kindling epileptic model ratsafter the success of rats with cognitive change detection performance, brain waves rats can collect a brain wave activity typical model, model makingsuccess rate was95.6%.Model1d group. Results through test of LT (53.72±3.51s), EN (3.69±1.17); group7d, passive avoidance test results for LT (44.51±1.28s), EN(4.15±1.18); group30d, dark avoidance test results of LT was (37.66±3.43s), EN as (5.44±0.49), sham operation group of dark avoidance testresults of LT was (53.14±3.11s), EN (3.55±1.51), blank control group dark avoidance test results of LT was (55.33±3.28s),EN (3.65±1.52). The model of rats in the model group compared with sham operation group the learning and memory ability significantly decreased (P<0.05, P<0.01), the comparison between the three groups, the rats in the model group1d,7d,30d group cognitive function decreased, with statistical significance (P<0.05, P<0.01), but were higher than normal group difference the ratio, were statistically significant (P<0.05, P<0.01).(1) Immunohistochemical results:Immunohistochemical GAP-43chemical staining results showedhippocampal cells into brown. The percentage of positive cells of kainic acid kindling epilepsy model group and blank control group had significant difference (P0.05), model group was significantly lower than that of the control group. Themodel group, the percentage of positive cells of30d was obviously lower than that of1d group,7d group,30d group was the lowest(P<0.05).(2) RT-PCR In the Marker control band is clearly visible, by measuring the opticaldensityvalue of each band, and GADPH housekeeping gene ratio proofreading,kainic acidkindled epilepsy model group and blank control group had significant difference (P<0.05), the model group was significantly lower than that of the control group. Compared with model group,30d was significantly lower than that in1d group,7d group,30d group (P<0.05).(3) Western blot blotting results:Expression of GAP-43protein in hippocampus of rats in each groupwere compared in the standard protein molecular, reference Marker, through the determination of the objective optical density with values, and β-actin house keeping gene protein ratio proofreading, kainic acid kindled epilepsy model group and blank control group had significant difference (P<0.05), the model group was significantly lower than that of the control group. Compared with model group,30d was significantly lower than that in1d group,7d group,30d group was the lowest (P<0.05).Conclusion1. Epilepsy can make learning cognitive function impaired memory rats kindled by kainic acid.2. Cut may be the molecular mechanism of impaired cognitive function. The expression of GAP-43in hippocampus of epilepsy rats kindled by kainic acid.