The Influence Of Hormone Therapy For Brain Death Donor Heart Myocardial Apoptosis

Background and objective:Heart transplantation has been regarded as the best way to cure terminal stage disease of the heart. However, the uniqueness of the heart, making the brain-dead donor heart is the main source of heart transplantation. Therefore, studying the changes of heart morphology and function in the brain-dead state may provide experimental foundation and theory basement for utilizing brain dead donor.After brain death, the central nervous system is losing control of the body, so the internal environment is lose of balance. The internal environment of BDD is different from the receptor, and the main factors is humoral regulation. Donor heart after brain death cause hemodynamic changes and biochemical cycle disorder, all this leading to myocardial apoptosis and myocardial damage. In recent years, the role of myocardial apoptosis in brain death after cardiac transplantation draw more and more attention.Hormone therapy is given hormones(Methylprednisolone sodium succinate, insulin) to the donor, to protect the function of donor'organ. This thesis is study the impact of hormone therapy on brain death heart after brain dead. Discuss the relationship between hormone therapy and myocardium cell apoptosis.Methods:To randomized 18 healthy Xishuangbanna miniature pigs into Sou-Medrol group and control groups and insulin plus Sou-Medrol group. The three groups were given general anesthesia and then earried on tracheotomy and tracheal cannula, mechanical assistance, internal carotid venous cannula, craniotomy and placed Foley balloon catheter into intracranial, by increasing intracranial pressure intermittently and slowly to build pig brain-death model. Ringer solution and Dextran-220 gived to the control group, methyprednisolone sodium succinate additional intravenous infusioned for the Sou-Medrol group. For the insulin plus Sou-Medrol group, monitoring of blood glucose, and use the insulin to control the blood gloceose blow 7 mmol/L. Each group were maintained for 10 hours. The histopathological change of myocardium was investigated by HE staining, and use electron microscopy to examine the ultrastructure, the myocardial cell apoptosis were detected TUNEL method and the ultrastructure of myocardial cell examined by electron microscope. The expression of FAS and BAX gene proteins were studied by PCR. Through these methods. All data were analyzed statistically using SPSS11.5 software.Result:1 after brain death and before cut the donor hear, the three groups occurred significant myocardial injury, manifested as myocardial cells and cell interstitial edema, and the gap increases, mitochondrial swelling, mitochondrial cristae fuzzy broken. Some cells showed nuclear shrinkage, chromatin broken into gragments, tend to the nuclear membrane, some part of the heart cross striation are unclear. And there are different degrees of dissolution or disappearance.2 after brain death and before cut the donor hear, methylprednisolone and insulin had no effect on myocardal cell apoptosis. There is no different between the three groups (P<0.05)3 after brain death and before cut the donor hear, methylprednisolone and insulin had no effect of the expression of FAS BAX on myocardial cell, there is no different between three grpups.Conclusion:1 Use slow and intermittent encephalic pressure increase to establish pig BD model is effectively. Brain dead model can be maintained stably for more than 10 hours. Effective respiration and circulation sustainting is the most important to maintained the model2 Brain death can lead to Banna miniature swine myocardial injury, as the time of brain death can occur morphological changes.3 Brain death can lead to Banna miniature pig cardiomyocyte apoptosis, and cause myocardial damage.4 Brain deat can lead to Banna miniature pig's apoptotic protein FAS,BAX levels increased, and cause cardiomyocyte cell apoptosis.5 After using methylprednisolone and insulin intervention the brain death process, apoptotic protein FAS,BAX levels remained unchanged, and the protection of myocardial is not affected by FAS,and BAX. 6 After using methylprednisolone and insulin intervention the brain death process, the apoptotic index did not change, the protection of cardiac function had no relationship with myocardial apoptosis.