Objective To investigate the effect of lung volume reduction surgery （LVRS） on messenger RNA expression levels of cytoskeletal proteins in diaphragmatic muscle tissues of emphysematous rabbits. Methods A total of 40 rabbits were randomly divided into 4 groups （10 rabbits in each group） ：normal control group, emphysema group, sham operation group and LVRS group. Rabbits in control group were intratracheally administered with 0.9% normal sodium, but those in other groups were intratracheally administered with 0.4% papain at the dose of 0.5 ml/kg and inhaled cigarette smoke to induce emphysema model. Then, rabbits in emphysema group were fed routinely, however, after median sternotomy , bilateral LVRS was performed in LVRS group but not in sham operation group. The mRNA expression levels of titin and nebulin in the diaphragmatic muscles of rabbits in each group were detected by reverse transcription-polymerase chain reaction（RT-PCR）. Results Compared with control group, the mRNA expression levels of titin and nebulin in the rabbit diaphragm of emphysema groups and sham operation group decreased significantly （P〈0.01 ）, so did those in LVRS group （P〈0.05）. But it increased significantly in LVRS group compared with emphysema group and sham operation group （P〈0.05）. Conclusion LVRS can increase the mRNA expression levels of titin and nebulin in diaphragmatic muscle tissues of emphysematous rabbits, which may be the associated mechanisms at the molecular level in restoring the functions of the emphysematous diaphragm by LVRS.
