Ianuzzo C D, Ianuzzo S E, Carson N, Feild M, Locke M, Gu J, Anderson W A, Klabunde R E
Deborah Research Institute, Browns Mills, New Jersey 08015-1799, USA.
J Appl Physiol (1985). 1996 Apr;80(4):1205-13. doi: 10.1152/jappl.1996.80.4.1205.
This study determined effects of surgical dissection and chronic stimulation on degeneration of the latissimus dorsi muscle (LDM), the muscle used for contractile assistance in cardiomyoplasty. LDMs from 10 goats were allocated into four groups: N-LDM (normal), D-LDM (dissected muscle and collateral vessels ligated, muscle remained in original anatomic location), S-LDM (electrically stimulated for 65-75 days), and DS-LDM (dissected and stimulated). S-LDM had nearly a complete transformation to type I fibers throughout the lengths of the muscle. Both groups of dissected muscles (D-LDM and DS-LDM) showed lesser transformation and significant damage. Type I myosin heavy chain and citrate synthase activity were less in the distal compared with the proximal LDM. Morphology of the N-LDM and S-LDM was normal, whereas dramatic morphological abnormalities were observed in the D-LDM and DS-LDM, including lipid-containing ghostlike fibers, atrophied and hypertrophied fibers within the same fascicle. In conclusion, muscle degeneration associated with the cardiomyoplasty procedure was caused by surgical dissection, which was exacerbated by chronic stimulation but was not caused by stimulation alone.
本研究确定了手术解剖和慢性刺激对背阔肌（LDM）退变的影响，背阔肌是心脏成形术中用于提供收缩辅助的肌肉。将10只山羊的背阔肌分为四组：N-LDM（正常）、D-LDM（解剖肌肉并结扎侧支血管，肌肉保留在原解剖位置）、S-LDM（电刺激65 - 75天）和DS-LDM（解剖并刺激）。S-LDM在整个肌肉长度上几乎完全转变为I型纤维。两组解剖后的肌肉（D-LDM和DS-LDM）显示出较小的转变和明显的损伤。与近端LDM相比，远端LDM的I型肌球蛋白重链和柠檬酸合酶活性较低。N-LDM和S-LDM的形态正常，而在D-LDM和DS-LDM中观察到明显的形态异常，包括含脂质的幽灵样纤维、同一肌束内萎缩和肥大的纤维。总之，心脏成形术相关的肌肉退变是由手术解剖引起的，慢性刺激会加剧这种退变，但并非仅由刺激引起。
