The Role Of Posynaptic Density In Rats Following Cerebral Vasospsam Injury After Subarachnoid Hemorrhage

Experiment purpose:1. Study after subarachnoid hemorrhage in delayed cerebral vasospasm in a rat modelof basilar artery diameter, the dynamic changes of the behavioral test, explore after SAH inrats cognitive dysfunction extent.2. Delayed cerebral vasospasm in rats studies after SAH, the PSD-95,N-methyl-D-aspartate receptor expression in the dynamic changes of the PSD-95andNMDAR in the delayed cerebral vasospasm after SAH injuryand cognitive impairment inthe role and possible mechanisms.Research Methods:1. In this study, Healthy adult Wistar rats were42applications cisterna magnaautologous arterial blood hemolysis material injected into the established SAH model.Random animals were divided into normal control group, sham operation group of SAHafter12h,1d,3d,5d,14d group.To observe the diameter of the basilar artery(BA) bySomatotype microscope and livingbody circulation measure system,the application ofMorris water maze behavioral testing, calculation of the average incubation period and thepercentage of the total swimming time in the platform quadrant swim time, the academicperformance of each group at different time points to detect.2. In this study, Healthy adult Wistar rats were42applications cisterna magnaautologous arterial blood hemolysis material injected into the established SAH model. Theanimals were randomly divided into sham operated and SAH groups,and each group wasrandomly divided into12h、1d、3d、5d and14d groups.The distribution and the dynamicexpressions of PSD-95and NMDAR were observd by optical microscope afterimmunohistochemistry staining.3. In this study, Healthy adult Wistar rats were42applications cisterna magnaautologous arterial blood hemolysis material injected into the established SAH model. Random animals were divided into normal control group, sham operation group of SAHafter12h,1d,3d,5d,14d group.Preparation of brain homogenates of animals in each groupafter the sucrose density gradient centrifugation, were extracted from the animals in eachgroup in cortex and hippocampus synaptosomes, Western blot analysis after full lysiscentrifugation Gelpro32analysis software to analyze samples of the PSD-95andNMDARexpress the amount of difference.Result:1. And compared to normal rats, SAH in the rat after appearing shaggy, feeding, lessexercise. Mental apathy, drowsiness, restlessness, standing instability, a head-down curledshape, in the nasal cavity can see dark red blood and eye hyperaemia.On SAH rats weresacrificed after observing the brain tissue, visible to the obvious subarachnoid hemorrhage,hemolysis mainly diffuse coverage in the skull base of major blood vessels, sella, posteriorfossa, the anterior cranial fossa. Each animal are no spontaneous brain hemorrhage orexperiment mechanical injury, hemolysis basic derived from autologous arterial blood.2. Sham operation group and model group after in vivo BA observation andtesting,results showed that compared with normal control group,sham operation group BAwas no significant contraction of the model group,BA obvious contraction spasm,thediameter is about the sham operation group42.2%.3. On the positioning and navigation test, on the first day of training rats in eachgroup there was no significant difference in escape latency, as the number of trainingincreases, the normal group and sham operation group rats latency in steady decline, andthe decreasing trend is obvious, and subarachnoid hemorrhage after five days and fourteendays of rats in training the very next day, cobweb subarachnoid hemorrhage three daysafter the rats in the fourth days of training showed significant mean latencyprolongation,compared with sham operation group difference has statisticssignificance(p<0.05).Space exploration experiments, the false operation group rats andnormal rats in platform quadrant swimming time percentage of no significant difference,subarachnoid hemorrhage after five days and fourteen days of rats in platform quadrantswimming time than the sham operation group rats in platform quadrant swimming timepercentage decrease(p<0.01).4. Under a microscope, PSD-95, NMDAR immune deposits are mainly distributed inthe cA1, cA3pyramidal cells and dentate gyrus of the cerebral cortex, followed by. In orderto membrane coloring, cytoplasm pale, brown granules, dendrites in expression. Semiquantitative analysis shows that, in the SAH group early transient elevated after PSD95, NMDAR expression gradually decreased, especially in CA1area, compared with shamoperation group, SAH5d group,14days was significantly lower, the difference wasstatistically significant(p<0.05).Application of Western blot on each hippocampal synapticprotein PSD95/NMDAR expression and semi quantitative analysis shows that, PSD95/NMDAR expression with time gradually decreased, compared with sham operation group,SAH5d group,14d decreased significantly, the difference has statisticalsignificance(p<0.05).Conclusion:1. Autologus arterial hemolysates injected into rat cisterna magna could induce stablymodle of SAH,model three days after cerebral vascular spasm occurred clearly visible.2. Subarachnoid hemorrhage delayed cerebral ischemia rat model after seven days canappear in different degree of cognitive dysfunction.3. After SAH in the rat brain cortex and hippocampus of PSD-95and NMDARexpression decreased gradually, with SAH5d,14d decreased after the most significant,showed that the PSD-95, NMDAR level and SAH after the occurrence and development ofDCVS correlation exists.Between PSD-95and NMDAR exists the synergy, PSD-95islikely to become the new target to treat cognitive dysfunction after the SAH.