The Role of MAPK Signal Pathway in Synthesizing Skeletal Muscle Protein of Rats Treated with Androgen and Exercise

［Abstract］Objective　To establish one week endurance exercise rat model，and put DHT sustained-release tablets in rat neck，explore the role of MAPK signal pathway in rat skeletal muscle protein synthesis induced by androgen and exercise．Methods　Twenty-four 8 week old male SD rats were randomly divided into four groups: sedentary control group（NC），exercise control group（SP），quiet and androgen group（NCD），exercise plus androgen group（SPD）；NC group and SP group was given sham operation，NCD group and SPD group was given DHT sustained-release tablets in neck；NC group and NCD group were given no special treatment，SP group and SPD group was given 7 days of treadmill training. After modeling，the total gastrocnemius muscle protein of rats were extracted and quantitatively examined， and the protein expression of ERK，p38，JNK was tested by western Blot. Results The total protein expression levels were increased gradually，and there was a significant difference in the gastrocnemius muscle total protein content（P＜0.05） with in NCD and SPD compared with NC group；in SP group， compared with NC group， the level of phosphorylation ERK， p38， and JNK were increased，and in sports and androgen coordination treatment group was the most significant. Conclusions　Androgen and exercise may increase the skeletal muscle protein synthesis，and the androgen could strengthen the effect of exercise on protein synthesis. Androgen and exercise may upregulate the expression of phosphorylated ERK，p38 and JNK in skeletal muscle，and SPD group is the most significant; it suggest that MAPK signal pathway may play a role in androgens and exercise.