The Effect Of Astragalus Injection On Neuronal Ultrastructure And Expression Of Apaf-1in Hippocampus Of Cerebral Ischemia Reperfusion Rats

Cerebral ischemia reperfution injury refers to the brain ischemia afterrestore blood supply in certain condition, emerged that more serious braindysfunction and structural damage, which are commonly seen shock, arterybypass, cerebrovascular embolization recanalization, open-heart surgery,cardiopulmonary cerebral resuscitation, etc. Ischemic cerebrovascular diseaseis the common disease in clinical neurology, which disability and fatality rateis high, the principal of treatment is to restore blood flow to the ischemic, butcaused the reperfusion injury at the same time, so restrain reperfusion injuryhas become an important link in treatment of ischemic cerebrovascular disease.Studies have shown that neuronal apoptosis is one of the importantmechanisms of cerebral ischemia reperfusion injury, and apoptotic-relatedgene Apoptotic Protease-activating Factor-1(Apaf-1) has most close relationwith neuronal apoptosis. Astragalus injection is commonly used to cure thisdisease, but the specific mechanism has not yet fully clear. So we establish therat model of cerebral ischemia reperfusion, based on the model and withastragalus injection, observation the effect of astragalus injection on neuronalultrastructure and expression of the apoptosis-related genes Apaf-1inhippocampus of cerebral ischemia reperfusion rats, discuss the mechanism ofinhibition of cerebral ischemia reperfusion.Aim:Observe the effect of astragalus injection on neuronal ultrastructure andexpression of Apaf-1in hippocampus of cerebral ischemia reperfusion rats.Methods:Clean gread healthy male SD rats divided into4groups: sham operationgroup, model group, astragalus injection group and original astragalus injection group. To reproduce animal model of the global cerebralischemia-reperfusion by4vessel occlusion. The model group, astragalusinjection group and original astragalus injection group was subdivided into7subsets, according to reperfusion times of0h,0.5h,2h,6h,24h,72h and120h, brains were removed after reperfusion at the appropriate time.Ultrastructural changes of hippocampal neuron were observed by electronmicroscopy; use immunohistochemistry and Western blot to detect theexpression of hippocampal neurons Apaf-1protein; the expression of Apaf-1mRNA was detected by RT-PCR.Result:The transmission electron microscopy results showed: The hippocampalneurons of the sham operation group, the nucleus large, round or oval, clearand complete nuclear membrane, euchromatin was finely evenly distributedand cytoplasm organelles was rich. The model2h group of hippocampal CA1neurons appeared nucleolemma introcession and chromatin densityincreased,as well as mitochondrial slight swelling; The model24h group ofhippocampal CA1neurons appeared nuclear membrane serious introcession,nucleoli material increased and deviated, rarefaction and vacuoles of themitochondrial structure, break of the mitochondrial cristae, rough endoplasmicreticulum degranulation; Karyopyknosis, mitochondria swelling and vacuolar,chromatin was set of edges the nuclear membrane in the model72h grouphippocampal CA1neurons could be seen. The astragalus injection2h groupof hippocampal CA1neurons appeared smooth of membrane structure,euchromatin was finely evenly distributed, mild swelling of mitochondria; Theastragalus injection24h group of hippocampal CA1neurons appearednucleolus shrinked improvement and nuclear membrance is smooth, chromatinsmall and scattered, cytoplasm swelling obviously improved; The astragalusinjection72h group of hippocampal CA1neurons appeared nuclear shrinkageis not apparent, nuclear membrance is smooth, chromatin small and scattered,cytoplasm swelling improved. Immunohistochemistry, Western blot and RT-PCR results show that: Except0h and120h, Compared with sham operation group, the expression of Apaf-1protein and mRNA at every time pointincreased obviously in model group (P<0.05). Compared to model group, theexpression of Apaf-1protein and mRNA at every time point decreasedobviously in astragalus injection group (P<0.05), however, the originalastragalus injection group had no obvious change (P>0.05).Conclusion:1. Rat hippocampal CA1area neuron appears obvious apoptosisphenomenon after cerebral ischemia reperfution,and astragalus injection canreduce neuron apoptosis.2. Astragalus injection can inhibit the expression of Apaf-1protein andApaf-1mRNA, and accordingly it inhibits apoptosis in hippocampal neuronsof cerebal ischemia and reperfusion rats.