The Protection Of Drug For The Myocardial Damage From Radiolesion

Objective: To investigate the change of the serum cardiac troponin T(CTn-T) and the ultrastructure of Ca2+ of the myocardial damage from radiolesion. And To investigate the protective effect of enalapril and diltiazem on myocardium.Methods: Make the rabbits model with myocardial damage due to radiolesion. Compare radiotropic group, drug group(enalapril), injection group(inject diltiazem), the change of CTn-T of control group. To investigate the change of myocardiol ultrastructure, To acknowledge the characteristics of the distribulation of Ca2+, the principle of tissue action and protective effect of enalapril and diltiazem on myocardium with the probe technique of 焦梯酸钾.Results: 1. Serum cardiac troponin T (CTn-T) increases with the dose of radiatio. The 3rd and 7th days after radiation, the mean of CTn-Tmakes positive correlation with the dose of radiatio.(r=0.789, P<0.001; r=0.780, P<0.01).The concentration of CTn-T(1500GY>1000GY>650GY) differs from the control group distinctively.(P<0.001; P<0.01;P<0.05). 2. CTn-T has increased three days afer radiation, and has inceased to the summit in the 7th day, and hasdecreased since the 14th day, and come back to the normal in the 21th day. However, CK-MB only increased in the 3rd day and in the the 7th day and keep normal in the the 14th ,21th, 34th day with no difference with the control group. The change of ultrastructure includes the disturbance of filament, partly resolution, asymmetry of mitochondria. Some expand. Some have no clear ridge. Even ridge rupture. Some mitochondria chang to vacuole. While the membrane is perfect, the calcium particles increase distinctly. While the membrane is damaged, the calcium particles disappear and mitochondria calcificate. 3. Drug group(taking enalapril): the filter of CTn-C decreases obstructively but increase in the 3rd day. It have no difference with the control group in the 7th , 14th , 21th, 34th day. However, CK-MB increases in the 3rd day and decreases in the 7th day compared with radiotropic group(P<0.01). It is different from the radiotropic group and have no difference with the control group. The expanding and vacuoled of mitochondria and musle resolving lessen obstructively. The disposition of calcium decreases. 4. Injectiongroup(injecting diltiazem): CTn-T begins to increase three days after injection. Later increase has no difference with the control group. Using sulfinpyrazone don't make CTn-T filter decrease obstructively, but make the expanding and vacuoled of mitochondria and muscle resolving anddespositon of calcium lessen distinctively.Conclusion: 1. The dose of radiatio makes positive correlation with CTn-T. 2. CTn-T have more specificity, sensitivity and duration for the diagnosis of myocardial damage than CK-MB. CTn-T can also reflect the extent of myocardial damage. 3. Enalapril has an obstructively proctective effect on myocardium,While diltiazem has less. 4. Lessing calcium overload of myocardial cells maybe one of mechanisms of enalapril protection for myocardium.