Expression Of CathepinB In Intracranial Aneurysms And Its Effect To Apoptosis Of Vascular Smooth Muscle Cell

Objection to observe the pathological changes of intracranial walls, to detect the expression of cathepinB(Cat B)in intracranial aneurysm wall and its effect to apoptosis of vascular smooth muscle cell.to reveal the pathological formation mechanism of intracranial aneurysm.Methods 20 specimens of resected intracranial aneurysms after microsurgical operation were the main research objects, and 6normal pallium artery specimens taken from traumatic patients after brain decompression operations as a control .The pathological changes were observed through hemotoxylin and eosin staining technique and light microscope .the ultrastruction wall of intracranial could be found out by transmission electron microscope.By applying the immunhistochemistry technique ,the expression of Cat B,a-SMA,caspase-3 in specimens could be detected and the index of intensity of the tissue could be graded. To analysis the relationship between the expression of CatB in aneurysm wall and clinical features such as Hunt﹠hess grade,aneurysm size, rupture or not ,intensity of cerebral vasopasm by statistical software.The expression of the CatB mRNA a-SMA mRNA could be measured by using quantitative real time RT-PCR technique.Results(1)HE stainingThe normal three -layer strucrt was lost in all of intracranial wall .The fundamental histopahological we can see in all of wall was the injured of endothelial cell;the number of endothelial cell decrease ; disintegration of internal of Elastic layer;VSMCs were scarce in the tunica media and dispalced by fiber tissue;infiltration of inflammatory cells;regional calcification,thrombosis and different stage of atherosclerosis in the aneurysm wall.(2)transminssion electron microscopeThe intracranial aneurysm wall defects the layer of muscle , the number of SMC decreased, the elastic fiber autolyzed;some SMC nucleus contracted completely or depressed,typical apoptosis body were seen in later stage.(3) immunohistochemistryThe expression of Cat B was up-graded in intracranial aneurysm groupcompare with in control group(260238.9±12343 52 .199751.4±11129.1 p<0.05); the expression of casepase-3 in aneurysms group was up-regulation compare with in control group(14366.1±10641.6,78580±5941.3,p<0.05); the expression a-SMA in aneurysms group is 174209.5±13596.4 lower than 2368 29.9±17981.3 in the control group P<0.05. the expression of CatB in aneurysms wall have spearman correlation with caspase-3, a-SMA,the and the size of aneurysm. The spearman correlation coefficients was,retrospec -tively ,0.82703, P<0.001 ;0.79844,P<0.001;0.7958,P < 0.001.But ,there was no correlation between the expression of cat B and patient's Hunt﹠hess grade,rupture or not,and intensity of cerebral vasopasm.(4)quantitative real time RT-PCRThe expression of cat B mRNA in IA group is 3.80097 folder of control group, P = 0.002221 < 0.01.The expression ofα-SMAmRNA in IA group is 3.91 folder of control group,P= 0.001854 < 0.01。Conclusion1 The patheological changes in aneurysms indicates that acquired regressive characte -ristics may contribute in the pathogenesis of intracranial aneurysm.2 The higher expression of catB in intracranial aneurysm walls indicates that CatB may take part in pathogensis of aneurysm。3 The expression of catB in intracranial aneurysm walls have spearman correlation with the size of aneurysm。4 The cathepinB may result in the formation and development of intracranial aneurysm by launching the mechanism of caspase system and induce the apoptosis of VSMC...