Sarcomeres Are Added in Series to Emphysematous Rat Diaphragm After Lung Volume Reduction Surgery

摘要: Study objectives The diaphragm adapts to its shortened state in experimental emphysema primarily by losing sarcomeres series, thus reducing optimal operating length. One would expect improved diaphragmatic function after lung volume reduction surgery (LVRS) only if the muscle can readapt elevated, lengthened postoperative position either adding back or lengthening sarcomeres. We used a model of elastase-induced rats test hypothesis that sarcomere addition occurs following LVRS. Design A cohort emphysematous was created intratracheal instillation elastase. Five months instillation, one group underwent measurement situ costal length via laparotomy, determination fiber (Lo) on stimulated strips vitro , and electron microscopy fixed at Lo. Another LVRS sham sternotomy 5 operation these animals same series studies. Results Lo significantly greater than those (mean [± SE] LVRS, 2.50 ± 0.08 cm; mean sternotomy, 2.27 0.06 p = 0.013). There no significant difference lengths between two groups (2.95 0.04 vs 3.04 μm, respectively; 0.10). Using as basis, number calculated be 8,712 192 had undergone 7,144 249 (p Conclusion Sarcomere is not altered but are added this emphysema/LVRS. It likely prerequisite improvement inspiratory has been observed humans.