Effects of tumor necrosis factor-? on metabolism of skeletal muscle protein in rats with chronic obstructive pulmonary disease and underlying mechanisms / 上海第二医科大学学报

ABSTRACT

Objective To study the effects of tumor necrosis factor-?(TNF-?) on hypermetabolism of skeletal muscle protein in rats with chronic obstructive pulmonary disease(COPD) and explore the mechanisms. Methods Forty-five SD rats were randomly divided into normal control group,COPD group and COPD +TNF-? group(n=15).Rat COPD models were established by passive cigarette smoking in COPD group and COPD +TNF-? group.After dissecting and isolating the extensor digitorium longus(EDL) muscles,the EDL muscles were either cultured with media containing 10 ug/L recombinant rat TNF-? or without TNF-?.The subsequent changes in ubiquitin mRNA and protein levels were determined by real-time quantitative PCR and Western blot,respectively. Results The expressions of ubiquitin mRNA and protein of COPD group and COPD+TNF-? group were higher than those of normal contro1 group(P