| Functional recovery after stroke has been associated with brain plasticity; plasticity means that the residual part of the nervous system after brain injury performs the lost function by new way duo to functional reorganization, definite rehabilitation training is essiential during the process. Neuroimaging studies in stroke patients indicate altered poststroke activation patterns, which suggest some functional reorganization. Reorganization, including intrasystemetic and infrasystemetic organization, may.be the principle process responsible for recovery of function after stroke. Experimental focal cortical lesions induce functional and structual changes in adjacent cortex, bilateral sensorimotor and visual cortex, basal nuclei, thalamus and cerebellum.People think highly of Early rehabilitation and contralesional hemisphere activation at present,. We investigated the mechanism of functional reorganization during early period of stroke by observing blood flow in different area of bilateral hemisphere during the ipsilateral, controlateral and bilateral electric stimulation in the forelimb at the level of wrist of postoperative rats and confirmed the difference of several electric stimulation by observing functional restoration of affected limb after different electric stimulation treatment.Material and method:1. Animal middle cerebral artery occlusion(MCAO) modelAdult male Wistar rats(n=100) Weighing 270-300g were employed in all experiments.the right carotid region was exposed through a cervical midline skin incision and division of the right omohyoid muscle for showing common carotid artery (CCA). The external carotid artery (ECA) was coagulated and divided after trimming the proximal ECA branches.the internal carotid artery (ICA) was then exposed and pterygopalatine artery (PPA) was ligated with a silk suture. After clamping the commonand internal carotid arteries, a small incision was made in the EGA and a monofilament suture with a rounded tip was introduced and advanced approximately 18.5 +0.5mm into the 1C A through the carotid bifurcation for proximal MACO.2. The experiment was devided into two stage.The first stage: In two separate groups of animals, radioactive counting experiments were performed at 3 days poststroke (n =32)and 14 days poststroke (n =32). In every group.the postoperative rats was equally devided into 4 subgroups: ipsilateral, contralateral, bilateral electric stimulation groups and control group. The different stimulation was performed in the forelimb at the level of wrist of the subjects with 6805-C electro-acupuncture apparatus at 3 days and 14 days respectively. After 10 minutes stimulation, 99mtc-ECD (100 ci) was injected into caudal vein. Rat brains were removed 5 minutes later and bilateral hemispere, infarcted area and its image area, motor cortex and cerebellum was separated. Radioactivity was assayed by counting meter and the ratio between tissue radioactivity and injected dosage(id%/g) was calculated.The second stage: the postoperative rats was devided into 3 groups: ipsilateral, bilateral electric stimulation groups and control group. Electric stimulation (4-5v, 0.5ms, 3 Hz, 30min per day, 1 course is equal to 7 days, 4 course continuously ) and behavioral testing(beam walking test) after every course was performed for the first and the second groups.3. Histological assessment36 poststroke rats were divided into 3 groups: ipsilateral, bilateral electric stimulation groups and control group. 4 animals in every group were killed at the end of 1, 2, 3 and 4 courses after stroke. In every coruse, 2 of them were perfused through the ascending aorta with prepared Chinese ink. At 10 minites after perfusion, rat brains were removed and fixed with 10% formaldehyde solution. After 1 week, coronal sections (100um) were cut on a vibrotome and dehyrated, then mounted onto glass slides; 2 animals were used for observing the infarct volume by TTC. The infarct volume was determined from seven slices (from 4.7 to -7.3 mm from bregma and expressed as a percentage...
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