Study On The Expression Of GAP-43in Hippocampus Of Ratsand Its Relationship With The Learning And Memory Of Hydrocephalus

Objective Establishment of hydrocephalus in the rat model of Sprague-Dawley, by avoiding hydrocephalus model rats were observed at different time on learning and memory function, detection ofnervegrowth associatedprotein (neuronal growth associate d protein, GAP-43) expression in brain tissue of rats with hippocampal hydrocephalus i n the rat model, to investigate the relationship between GAP-43and learning and m emory.Methods1.A correlation with learning and memory in rat model of hydrocephalusSprague-Dawley:healthy male SD160rats, were randomly divided intomodel of hydrocephal us hydrocephalus group, sham operation group,normal control group, model of hydroce phalus components1W,2W,4W,6W, a total of4sub groups, sham operation group on lyoperation, saline injection, not into the kaolin suspension, blank control group and mo del group, sham operation group and the samefeeding environment, each matching the re lative number of normal rats as control. The behaviors of all rats were observed, with passive latency record each rats method (LT) and shuttling back and forth times (EN), to study the learning and spatial memory function. The relationship between the exp ression of learning and memory in rat hippocampal GAP-43of rats:single cage feedin g, passive avoidancetest, no external stimuli were killed painless hydrocephalus model group and8rats in the sham operation group and blank control group8rats, the re maining rats into the next sub group. Hydrocephalusmodel group every subgroup dark a voidance test in1W,2W,4W,6W at different time points in rats were killed, in each time point of model group rats n=24, sham operation group and blank controlgroup n=8; detec, and take of the hippocampal of GAP-43mRNA and protein expression.2/3ra ts in each group were anesthetized rats, the rapid hippocampal tissue was taken out, p laced in a freezing tube, in liquid nitrogen after the move to-80℃refrigerator to spar e, and another1/3under ether anesthesia with4%paraformaldehyde perfusion after wh ole brain radiotherapy in sucrose solution were gradient overnight dehydration,applicatio n of OTC (Sakura, USA) embedding,-80℃refrigerator fortissue sections.2. Relationship between expression of specimens byimmunohistochemistry, RT-PC R and Western blot technology to study the spider hydrocephalus in hippocampus of ra t model of GAP-43mRNA and protein and study of learning and memory。Result(1). hydrocephalus model rats after the success of cognitive changes in rats after b rain waves, detection of rat can collect a brain wave activitytypical model. The success of the model was95.6%. The blank groupdark avoidance test results of LT was (55±3.78s), EN (3.65±1.52),model group, model group:after the success of the1W model.Through test of LT (51.73±3.62s), EN (3.89±1.07); hydrocephalus model group2W dark avoidance test results for LT (44.51±1.28s), EN (4.35±1.19); hy drocephalus model group4W dark avoidance test results of LT was (37.86±3.57s), EN (5.71±0.49); hydrocephalus model group6W dark avoidance test was (31.22±3.18s), EN (3.96±1.37times), sham operation group dark avoidance test results of L T was (53.14±3.1Is), EN (3.55±1.51) hydrocephalus model of rats in the model g roup and the control group were lower than those in the learning and memory abilit y (P<0.05), the comparison between the two groups, the rats in the model group1W,2W,4W,6W group cognition function gradually weakened, the learning and m emory is significantly reduced, with statistical significance (P<0.05), as compare d with normal group, the ratio was statistically significant (P<0.05),(1) immunohist ochemical results:GAP-43immunohistochemical staining results showed hippocampal c ells into brown. The percentage of positive cells of hydrocephalus model group and b1ank control group were significantly different (P<0.05), model group was significant lylower than that of the control group. The model group, the percentage of positive cells of6W was obviously lower than that of1W group,2W group,4W group was th e lowest (P<0.05).(2). RT-PCR in the maker controls to strip is clearly visible, by measuring the opti cal density value of each band, and GADPH housekeeping gene ratio proofreading, brai n water model group and blank control group had significant difference (P<0.05), th e model group was significantly lower than that of the control group. Compared wit h model group, the optical density value of1W,2W, ignition proof4W group was signi ficantly higher than that in6W group,6W group was the lowest (P<0.05).(3). Western blot blotting results:the expression of GAP-43protein in hippocamp us of rats in each group were compared in the standardprotein molecular, reference make r, through the determination of theobjective optical density with values, and β-actin hou sekeeping gene protein ratio proofreading, hydrocephalus model group and blank co ntrol group with significant difference (P<0.05), the model group was significantly lower than that of the control group. Compared with model group, the optical den sity value of1W,2W, ignition proof4W group was significantly higher in6W gro up,6W group was the lowest (P<0.05)Conclusion1. Hydrocephalus rats model was established successfully,hydrocephalus mode1rats learning and memory impaired cognitive function.2. The down-regulation of GAP-43expression in brain tissue of rat hippoca mpus hydrocephalus, may be an important molecular mechanism of learn ing and memory.