Hypertension And Abnormal Hemodynamics Cause Pathological Changes In Cerebral Blood Wall Injury On The Animal Experiments

ObjectiveTo discuss the relationship between experimental rat hypertension and abnormal hemodynamics and pathological changes in cerebral blood wall damageMaterial and method1. SubjectSelection of 40 male SD rats, aged 4 W-6W, weighing 150-250 grams, animals and animal by the China Medical University laboratory animal experiments Shengjing Hospital Center. 2.Experimental methods(1) animal groups40 SD rats were randomly divided into experimental and control groups: The experimental group: SD 30 rats, all left common carotid artery ligation + abdominal median line approach after the renal artery-coagulation + 10% after one week instead of saline water one week one percent drip feeding;Control group: SD of 10, not to make any deal with, the normal feeding(2)rat tail artery blood pressure measurementsAll in one day before the measurement of blood pressure as a basis of blood pressure, the experimental group and control group and were in operation after two weeks, six weeks, 12 weeks measuring blood pressure.(3)specimens of cerebral vascular accessAfter 12 weeks, all the rats under general anesthesia (as above) to open, detection of renal renal artery after back-supply situation in parts of ischemia rapidly after thoracotomy, intubation through the left ventricle to the aorta or, to use physical 30 ml Transcatheter saline infusion, at the same time cut emissions vena cava blood, and then use more than four percent of POM / 0.1M phosphate buffer (pH7.4) 120ml slowly into the catheter, then rats and appeared pale limbs twitching And cramps, head and neck gradually become rigid and that infusion effective, will be fixed when the infusion of broken neck, craniotomy for brain surgery in 10 to 16 times under the microscope will be removed from Willis Central carefully, and then at 40 times the microscope Central inspection Willis, in particular the right of a brain artery olfactory artery (anterior cerebral artery-ol-factoryartery, ACA-OA) section of vascular changes.(4)erebrovascular samples of light microscopy10% formaldehyde fixed, alcohol gradient dehydration, paraffin-embedded sections, conventional HE staining.(5)cerebrovascular electron microscope examination of the specimensCerebral vascular specimens will be immersed in the 2.5% glutaraldehyde-fixed 24-hour, one percent of the four fixed hungry again, step by step acetone dehydration, Epon812 embedded, semi-thin slices of optical positioning, ultra-thin slices of uranium and acetic acid structure Chuan lead acid double staining, thin slices with H-600IV TEM observation, film.(6) specimens of cerebral vascular TUNEL staining reagents and light microscopyEmbedded in paraffin sections of the conventional pretreatment dewaxing dehydration, with protease K (20μg / ml dissolved in Tris / HCl in, pH7.4～8.0) incubated at room temperature 15 to 30 minutes. Or pepsin or trypsin (0.25%～0.5% HC1 solution) 37℃incubated 15 to 60 minutes. PBS washing 2, the last light microscopy analysis of the results.3. statistical methodsStatistical analysis using SPSS for Windows 10.0, P <0. 05, the difference was significant.Results1. survival30 survived the test group 24, all of the normal control group survived. Six mice died.2. blood pressure changes Since the experimental group than the two weeks since the control group were significantly higher blood pressure, blood pressure rose steadily after. Normal control of blood pressure is maintained in the normal range. Variance analysis results: the experi-mental group and control group, blood pressure are significant differences (P <0. 01)3.Light change12 SD rats vessel walls that have different degrees of change, especially cerebral vascular ACA-OA bifurcation the vessel wall endothelial cells disappear, elastic membrane within the hierarchical and bifurcation of the distal end of a broken elastic panels, wall However, no significant mild thinning of the wall outside the process; smooth muscle cells of different sizes, with disorder, a decrease in the number.4.electron microscopy and the observation of TUNELElectron microscope 12 that the experimental group as early as mid-August only change, smooth muscle cells very irregular shape, nuclear heterochromatin agglutination and near the nuclear membraneset, nuclear gap widened, almost swallow the cap-sule to drink more vesicles . In-situ TUNEL apoptosis detection kits vascular smooth muscle wall of apoptosis, an average of 50 per high power field of apoptosis cells for apoptosis index (TUNEL index TI). The experimental group TI = 3.83±1.47, the control group TI = 0.6±0.2, both statistically significant difference, P<0.01.DiscussionHigh blood pressure and can cause anomalies hemodynamics wall of varying degrees of cerebral blood injury, and this may damage the vessel wall to become intra-cranial aneurysms in the early change. Intracranial aneurysm is a common human brain diseases is one of the spontaneous subarachnoid hemorrhage caused by the first reason, the disease is the most important feature of the high morbidity and mortality. Bleeding in patients, about 1 / 3 in attendance before the dead, 1 / 3 die in the hospital, only 1/3 were treated and survived . large number of foreign literature aneurysm bleeding after the mortality rate as high as 40 percent to 50 % And high morbidity , Peters data show that the incidence in patients with cerebral aneurysms rupture at that time or soon after mortality rates as high as 50 percent in the remaining 25 percent, such as paralysis, aphasia, blindness and movement Total economic barriers, such as the permanently disabled while 25 percent are still bleeding and other complications of high risk. In view of intracranial aneurysm is a serious threat to peoples lives and health of a disease, reported in the literature of vascular smooth muscle cells in the wall lead to apoptosis aneurysm is the major factor, vascular smooth muscle wall of apoptosis is extremely important research on the clinical And social values.This study has proved that in the electron micro-scope and were detected by TUNEL arterial smooth muscle apoptosis in a cell membrane. Electron microscopy irregular-shaped smooth muscle cells, nuclear heterochromatin condensate and a more integrated block-set, that the nuclear-vesicles. Light microscope vascular endothelial cells wall shrinkage or degeneration, osteoporosis, elasticlayered or completely dis-appeared, vascular smooth muscle cells in the wall of apoptosis.By ligation of the left carotid artery, bilateral renal artery and one percent after the drip-feeding rat animal model of hypertension, and to observe the electron microscope vascular smooth muscle cells in the wall apoptosis and TUNEL reagents observed changes in apoptosis, it may be inferred that hypertension And hemodynamic changes arising from the vessel wall apoptosis increased, resulting in vessel walls stretch of the large number of destruction, and the formation of aneurysms are closely related.ConclusionBy ligation of the left carotid artery, bilateral renal artery and one percent after the drip-feeding animal model lead to hypertension, and were observed in the light of a cerebral artery bifurcation the olfactory artery vessel wall changes in the electron microscope vascular smooth muscle wall TUNEL reagents and apoptosis observed changes in apoptosis, it may be inferred that hypertension and abnormal hemodynamics of the vessel wall will cause damage, and with the occurrence of intracranial aneurysms and their development are closely related.