Abstract：The mRNA expression of muscle development and energy metabolic related genes were investigated by inhibiting janus protein-tyrosine kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3) signal pathway using AG490. The tentative male Kunming mice (Mus musculus) were treated as intraperitoneal injection of AG490 for two weeks. After execution, the leg muscled was surgically removed and total RNA was extracted. Real-time quantitative PCR was used to examine the mRNA expression of the key factors in JAK2/STAT3 signal pathway JAK2 and STAT3, the growth relative genes of skeletal muscle myogenic determination（MyoD）and myogenic factor 5 (Myf5）, and energy metabolic relative genes Liver X receptors（LXRα）and Uncoupling proteins (UCP3）. Compared with control, the body weight of mice were significantly decreased (P＜0.05); the body temperature was stable; the expression of JAK2 and STAT3 mRNA were significantly decreased（P＜0.05）; the expression level of LXRα, UCP3, MyoD5 and Myf5 mRNA were decreased extremely significant(P <0.01). JAK2/STAT3 signal pathway may regulate the growth of skeletal muscle and energy metabolism by decreasing the mRNA expression levels of the growth of skeletal muscle development and energy metabolic relative genes.
