Study Of The Effect Of Treadmill Training On Angiogenesis In The Injury Region In Rats With Focal Cerebral Ischemia

Chromogranin A (CGA) is widely distributed in the neuroendocine system and considered as a diagnostic marker of the whole activity of neuroendocrine system. A neuroendocrine activation has been described in the process of dilated cardiomyopathy, which promotes the myocardial cell apoptosis, the stimulation of myocardial interstitial collagen hyperplasia and remodeling, and the imbalance of collagenⅠ(COLⅠ)and collagenⅢ(COLⅢ). Losing the support of collagen, the function of left ventricular coverts from pressure pump to capacity, and eventually lead to heart failure. The CGA are released by sympathetic nerve terminals and counteract the actions ofβ-adrenergic drugs. It is also showed that CGA can modulate fibroblast cell adhesion and spreading in a differential manner. Catestatin is one of active polypeptides of CGA and an antagon of catecholamine. So it is speculated that CGA, especially its active polypeptides catestatin, could also contribute to regulate heart remodeling in patients with DCM. However, the correlation between CGA and myocardial fibrosis and the mechanism of its effects on myocardial fibrosis remained uncertain. In the present study, the expression and location of CGA and myocardial fibrosis in DCM were observed, and also the mechanism of myocardial fibrosis related with CGA and catestatin was studied, so as to give rise to the further study in the role of the neuroendocrine of DCM and clinical evaluation of myocardial fibrosis.PART I The protective effect of treadmill training on angiogenesis in the injury region in rats with focal cerebral ischemiaObjective To investigate the effect of treadmill on the appearance of angiogenesis in short-duration focal ischemia in rats brain.Methods-The authors induced left middle cerebral artery (MCA) occlusion in male SD rats by insertion of an intraluminal suture.18 rats were divided into 3 groups:sham group; control group; treadmill training group. After 2 weeks, rats were killed and the angiogenesis was examined histochemical examination.Results. The data indicated that the total number of apoptotic cells increased in control group contracted to the sham group but without significance; In the treadmill group the number increased significantly contrasting to the other two groups(p<0.05). Conclusion.Treadmill training can enhance the appearance of angiogenesis in the injury region in rats with focal cerebral ischemia.PARTⅡ:Study of the Effect of Treadmill Training on Angiogenesis via Tie-2/Pi3k/Akt Pathway in the Injury Region in Rats with Focal Cerebral IschemiaObjective To investigate the effect of treadmill on the appearance of angiogenesis via the PI3K/AKT pathway in short-duration focal ischemia in rats brain.Methods,The author induced left middle cerebral artery (MCA) occlusion in male SD rats by insertion of an intraluminal suture.30 rats were divided into 3 groups:sham group; control group; treadmill training group. After 2 weeks, rats were killed and the angiogenesis was examined by means of immunohistochemical examination. The expression of Tie-2,total-AKT/ phospho-AKT was examined by Western Bloting.Results.The data indicated that the angiogenesis and the expression of Tie-2,phospho-AKT increased in control group contracted to the sham group but without significance; In the treadmill group the number increased significantly contrasted to the other two groups (p<0.05). The expression of Tie-2,phospho-AKT also increased significantly contrasting to the other two groups (p<0.05). In these three groups, there was no significant difference about the expression of total-AKT. Conclusion:Treadmill training can enhance the appearance of angiogenesis in the injury region in rats with focal cerebral ischemia via up-regulating the expression of Tie-2,total-AKT/phospho-AKT.PARTⅢ:Effects of treadmill training on angiogenesis and apoptosis after cerebral infarction in rats brainObjective:To investigate the effect of treadmill on the appearance of apoptosis and angiogensis in short-duration focal ischemia.Methods:The authors induced left middle cerebral artery (MCA) occlusion in male rats by insertion of an intraluminal suture. The total number of apoptotic cells was determined by hematoxylineosin staining and TUNEL labeling and confirmed by gel electrophoresis. The angiogenesis was examined histochemical examination;Results:The data indicate that the total number of apoptotic cells increased with ischemia duration, but in the treadmill group the number decreased significancely. Weatern boltting showed that a significance increaseof the expression of Bcl-2 in treadmill groupcontrst to the other two groups.Conclusions:Treadmill training can enhance the appearance of angiogenesis, reduce the apoptosis of cells. And this study also suggested that treadmill can reduce apoptosis by enhancing angiogenesis.