| Obsjective:Though there are so much of studies about protection of exercise to cardiovascular disease ,especially to diabetes,it's still unknown that what protective mechanism it is. It's still initial that the study about calcium ion channel which is in the intervention of exercise and on the state under the shyperglycosemia and oxidative stress. In this study we investigated the effect of exercise to sarcoplasmic reticulum calcium modulin---SERCA2,PLB and RYR---of myocardium of diabetes rat ,including the expression of mRNA and protein by setting up the modle of 1 type diabetes rat, the result can be used to establish the experimental basis for its clinical application.Methods:All the rats were randomly divided into four groups: normal control group; Exercise training group, diabetes group and diabetes with exercise-training group. Rat were injected with streptozocin , ,and the control group was injected with citric acid buffer solution only. Before exercise training, the blood glucose level was measured with a drop of blood collected from the tail by using glucose test strips. The animal was exclude from diabetic group if the level of blood glucose was less than 16.7mmol/L.At the end of 4- week-exercise training after the injection, the animals were killed and the level of blood glucose,insulin,blood fat and glycosylated serum protein were tested .The hearts were rapidly removed and washed in ice-cold 0.9% NaCL solution, and the atria and aorta were cut off. A littlt tissue at the apex was obtained for HE dyeing study. The ventricles were freeze-clamped and grind wih liquid N2 .The gene expression of calcium modulin proteins was measured by reverse transcription-polymerase chain reactionTo measure transcription of SERCA, PLB and RyR2 calcium channel,semiquantitative RT-PCR was performed. Total RNA was extracted with TRIZOL Reagent.The quality of RNA content was assessed by Electrophoretic diagram by agarose gel . A quantity of 5μg of total RNA was reversetranscribed in a 25μl reaction mixture .For PCR 2ul of the cDNA mixture was added to 25 ul of a master mix.PCR products were separated on 1.5% agarose ethidiutm-bromide gel, visualized under ultraviolet ligh.And use the western-blotting to measure the protein of SERCA2 and PLB.Results:The level of biochemical indicator of exercise group is not affected in exercise group contrast with control group,but signiffcantly changed in diabetic group(P<0.01),after exercise training , blood glucose,insulin,blood fat and glycosylated serum protein was ameliorated in diabetic with exercise training group. it proved that exercise can improve the metabolic disorder of lipidObservation of histological sections of myocardium stained with HE under light microscopeshows shows that muscle fiber fretrogression alteration, muscle fiber fragmentation,muscle bundle grudge widen, vessel wall thickening, intracavitar blood decreased, basal laminais is not integrity in diabetic hearts.,but it's not so seriously in diabetic with exercise training group ,which suggested exercise training can protect the heart against the diabetic cardiomyopathy.No changes in mRNAs level of SERCA2, PLB and RYR2 calcium chaimel were observed between control and diabetic group,the same to protein expression of SERCA2 and PLB. But Expression of calcium chaime mRNAs was significantly increased in exercise group and diabetic with exercise training group contrast with control group and diabetic group(P<0.01), the same to protein expression of SERCA2 and PLBConclusion:1. the level of blood gluclose is higher than 16.7mmol/L in diabetic group and diabetic with exercise training group ,which means the modle of 1 type diabetes rat has been established successfully.2. Gene expression of calcium modulin in diabetic rat heart was changed suggest the protective mechanism of exercise is relative with the up-regulation of the gene expression of SERCA2,PLB和RYR2.
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