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Purpose:FAT/CD36 is a transport protein of muscle.Recent evidence supports that FAT/CD36 has an important role in uptake of fatty acids in muscle.Some evidences have emerged that changes of lipid metabolism will influence FAT/CD36’ s distribution in muscle cell.Exercise and high-fat diet have been shown to regulate lipid metabolism with different mechanism.The present study investigated the effect of endurance training and high-fat diet on FAT/CD36 protein expression and discussed the potential mechanism of fatty acids transport in skeletal muscle whole homogenates and mitochondria.Method:male Sprague-Dawley rats were randomly assigned to four groups: sedentary + chow group,SC(n=10);sedentary + high-fat diet group,SF (n=10);Train + chow group,Tc(n=15);Train + high-fat diet group,TF (n=15).Rats in train groups were taken endurance train for 7 weeks;rats in high-fat groups were fed with high-fat diet(40%KJ fat) for 7 weeks. At the end of the 7th week,blood and rectus femoris samples were collected, and blood glucose,serum insulin,serum glucagons,serum blood lipid, muscle whole homogenate and mitochondrion FAT/CD36 protein expression were determined.Result:after 7 weeks’ training,rats in train groups have less fat content(p＜0.001),lower blood glucose,serum blood lipid,serum insulin level(p＜0.001,p＜0.05,p＜0.001,respectively).FAT/CD36 protein contents were elevated,in both whole homogenate and mitochondrion(p＜0.01,p＜0.01,respectively).After 7 weeks’ high-fat diet,rats in high-fat diet groups have more body fat(p＜0.05),higher glucose,serum total cholesterol,HDL-C,LDL-C level(p＜0.01,p＜0.001,p＜0.05,p＜0.001,respectively).FAT/CD36 protein contents were elevated in muscle whole homogenate(p＜0.05),but contents in mitochondrion have no significant(p=0.968).Gain efficiency of high-fat diet was significant higher than chow diet(p＜0.001).Conclusion:After 7weeks-training,the levels of rats’ body fat,glucose, serum blood fat,serum insulin are low.Rectus femoris whole homogenate and mitochondrion FAT/CD36 protein contents are up-regulated to meet the needs of fatty acids transport.After 7 weeks-high-fat diet,rats’ body fat,glucose,serum total cholesterol,HDL-C,LDL-C contents are high. Rectus femoris whole homogenate FAT/CD36 protein contents are also increased to meet the needs of whole body’s lipid metabolism,but because of the low level of lipid catabolism,FAT/CD36 protein contents in mitochondrion had no significant change.
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