| The model of focal ischemia is one of the most important method to investigate ischemic cerebrovascular disease for all of its optimization, such as it can imitate some complicated risk factors and courses of pathophysiology of disease, it can be building immediately and stimulate blood drawdown or blocked.the degree of ischemia is equal and so on. Meanwhile we also can control the state. However, there mainly are some defect in making a perfect model. recently, it is popular to use a strand of line to block the blood of MCA instead of transcranial operation .this way holds to control accurately the time between ischemia and reperfusion, which result is reliable.Nevertheless, its handing and complication like bleeding requst to investigate the lengthen,diameter,methord of making line head,weight of animals and its ages deeply.In our research ,we have compared three operations as external carotid artery(ECA) ,internal carotid artery(ICA) and carotid artery common(CCA)patching to build the model of cerebral ischemia in rats. We study the effect some factors like rat weight and epistomium on model of MCAO. All of those work are mainly to complement this model, investigate the principle of the MCAO made by patching thread ,then find more suitable one to our research.Partone:A total of 45 male Sprague-Dawley rats (90d, weight 300～350g ,grade SPF) were divided in to three groups randomly. Then three operation(ECA,ICA,CCA patching) were executed on each of group.Part two:Animal were provided by the same institute to part one .there were also three group in this part. 15 male SD rats were in each of group . they were group one 75d with weigh on 240-270g,group two 90d with weigh on 320-350g,group three 105d with weight 420-450g. they were all treated by CCA patching operation.Part three:A total of 30 male SD rats (90d,weight 320-350g)were divided in to three groups,they were accepted to the same operation CCA patching but the coverage of gel silica on head of thread embolus was different.(1mm,3mm,5mm).The rats were evaluated by neuroethology analysis and weight were got everyday.rats were anesthetized with 10％choral hydrate in normal saline(3ml/100mg, intraperitoneally)to inmobilized with either and sacrificed with an intracardacinjection of ice normal saline .Brains were removed rapidly and within 3 min of death coronal slices were made at over 2mm, about 5～7 slice. sections were immersed in 1%2,3,5-triphenyltetrazolium chloride(TTC)for stain.Result:1. through comparing three patching method of ICA,ECA and CCA, we acquired that the neuro-behvior assessments and cerebral infarction are both have significant difference between model group and control group(p<0.01),but not between three methods. It manifestations that three methods mentioned above are all able to build the model of MCAO successfully, neuroethology assessments make no different between them as well. Howerer, patching trough CCA is the better way for it is just ligating one artery, no damage to nervus vagus and other tissue. Wound during this operation is small, little bleed and shorting the time of operation makes it easy to handing.2. The effects of ages and weight on model. There are no significant difference on success rates between three method (p>0.05); whereas, group (weight320-350g)is lower than group(weight240-270g) on the death rates of 7 days, which has significant difference(p<0.05).The weights of model rats was decrease on different degree during 5 days after operation . the lower weights of group(240-270g) during ld,3d and 5d after operation are as follow:27.3±2.1g,56.7±3.7g and 66.5±2.6g; the second group(320-350g) lowing weights during ld,3d and 5d after operation are:17.3±2.6g,51.4±3.4g and 65.5±3.6g ; the last group(420-450g) lowing weights are displayed as:30.8±2.1g,71.4±4.5g and 75.9±3.9g. Rats weight on control group are also decrease 5.6±1.8g during 1d after operation, but rised the following days as 5.4±2.1g (3d) and 17.1±3.2g (5d) there is a significant difference between model group and control group(p<0.05). It illustrates that cerebral ischemia instinct effect animal health Given determinate line epistom, animal (90d,weight320-350g) have lower change on weights during early days after operation. They are more easy survival.3. effection of line epistom on model. Group(diameter of line epistom=3mm) have a significant difference on death rates of 48h after operation and model achievement ratio compared with group(5mm)(p<0.05). Group(3mm) is lower on death rates but highter on model achievement ratio. Group (1mm) is lower to group(3mm)and group(5mm) on volume of cerebral infarction, which have a significant difference(p<0.05).Conclution:1. Compare with traditional method ECA patching and ICA patching to made model of MCAO, improvement method as trough CCA patching is more easy to handle. This method guarantee experiment animal have a long term survival through shorting time of operation and growing downwards operation wound. The model also have fixed ischemia location ,the neuroetholigy assessments and cerebral infarction volumes are at equal place.2. Group(320-350g) have high achievement ratio and low death rates during 7d after operation. According to our investigation, to build model with high achievement ratio, rat weight at 320～350g is the optima choose. Meanwhile,weights of Modle rats can help to assess whether the model is successful.3. Optimal length of gel silica covered the head of line epistom is 3 mm. 5mm cover makes higher model achievement ratio and higher death rates during 48h after operation yet. There is a significant difference on cerebral infarction volume between 5mm cover and lmm cover, which indicated too extent cerebral infarction may to high death rates. So much evidence shows that neurorehabilitation have played a very positive role in the cases of improving the nervous system disorder and enhancing the abiliy of daily living self-care and the quality of life. For the past few years ,the development of apoplexy neurorehabilitation is so rapid in our courtry ,whereas the disorder, randomness, and even the lack of effective proof in the recovering technique have became serious situation in stroke rehabilitation process of China.Objectives:The application of acupuncture stimulation on the MCAO model rats which are in the early phase of focal cerebral ischemia provides empirical basis when we evaluate the effct of stimulate training the normal limbs ,when we investigate "time window" of early intervention, the interventions means in the rehabilitation and ultra-early intervention, and when we evaluate the effciency of electroacupuncture stimulation in rehabilitation training, as well as when we study the cross-migration theory and Chinese Medicine "JU CHI" theory.Methods:After the establishment of the permanent middle cerebral artery occlusion (MCAO) by carotid artery interpolation,160 MCAO (after 3 h and 24 h Bederson score 1 to 3, as modeling success) SPF-SD rats were randomly divided into four training groups with different period (3 d, 7 d, 14 d and 21 d), each group has 40 rats; and then, the 40 rats were also randomly divided into disability training(DT) group, health training(HT) group, Model control(MT) group and the operate control(OT) group, each group has 10 rats. Treat each group with EA every day, monitor rats'weight and evaluate the neuroethology. Record the amount of death in each group. Pour ice PS into left ventricle before take out the rat brain. Each slices 2mm, TTC stained and IPP analysis the volume of brain ischemic. All data were statistical analysis by SPSS, measurement data use t test, numeration data use x2 test, ranked data use rank-sum test. Conclusion: EA should not deliver immediately after the onset of brain ischemic, at least after 3h, 24h is suitable. Intervention of rehabilitation therapy too early may increase brain damage.EA on the limb of the health side on early period of onset is effective. EA can amendments the neuroethology of rats and at the same time do not increase the volume of cerebral infarction.EA can significantly improve after cerebral infarction the capacity of balance and coordination of rats after cerebral infarction, and promote the restoration of motor function.The volume of cerebral infarction and mNSS score are two credibility indexes in evaluating the effect of rehabilitation of MCAO rats; Bederson score is not suitable; beam-walking test and bilateral forepaws grasp can be evaluated the Strength and balance function, but needs to be further refined; muscle wet weight is a meaningful indicator, but not precise enough in this experiment (0.1 g).
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