Wu Yanqiu, Chai Jiake, Sheng Zhiyong
Burns Institute, 304th Hospital of People's Liberation Army, Beijing 100037, China.
Zhonghua Wai Ke Za Zhi. 2002 Mar;40(3):219-21.
To observe the changes in proteolytic rate and the influence of escharectomy and skin-grafting during shock stage on the proteolytic rate of skeletal muscle in severely scalded rats, and to investigate necessity of escharectomy during shock stage.
Wistar rats afflicted with 30%TBSA (total body surface area) full-thickness burn on the back were randomly divided into 3 groups: burn injury group (group B), escharectomy during shock stage group (group S), and escharectomy after shock stage group (group N). Escharectomy and skin-grafting was performed on the postburn day 1 (PBD1) and PBD4 in group S and N. The extensor digitorium longus (EDL) muscle was collected using a technique without injury to the muscle, and the proteolytic rate of the EDL was determined by the in-vitro muscle incubation system with sufficient oxygen supply and amino acid automatic analyzer.
The total proteolytic rate (TPR) in rat EDL muscles increased significantly (t > 2.988, P < 0.01) on PBD1, but no prominent changes were observed at other time points. There were no statistically significant changes in TPR between group S and group N, but the myofibrillar proteolytic rate (MPR) in rat EDL muscles increased markedly at each time point after scald (t > 2.988, P < 0.01). The MPR in group S decreased significantly as compared with that in group N on PBD2, 4, 5 (t = 2.311, P < 0.05; t = 3.054, 3.319, P < 0.01), and the mean values were 3.17, 2.33, 1.75 nmol/wet weight in g/3 h, respectively. No significant changes were observed between group N and S.
The high protein catabolism of skeletal muscle can be alleviated by escharectomy and skin-grafting during shock stage, and it is beneficial to organics.
观察严重烫伤大鼠休克期骨骼肌蛋白水解率的变化以及休克期切痂植皮对其蛋白水解率的影响，探讨休克期切痂的必要性。
将背部30%TBSA（总体表面积）全层烧伤的Wistar大鼠随机分为3组：烧伤组（B组）、休克期切痂组（S组）和休克期后切痂组（N组）。S组和N组于伤后第1天（PBD1）和PBD4行切痂植皮术。采用无损肌肉技术采集趾长伸肌（EDL），通过充足供氧的体外肌肉孵育系统和氨基酸自动分析仪测定EDL的蛋白水解率。
大鼠EDL肌肉总蛋白水解率（TPR）在PBD1时显著升高（t>2.988，P<0.01），其他时间点无明显变化。S组和N组TPR无统计学显著变化，但烫伤后各时间点大鼠EDL肌肉肌原纤维蛋白水解率（MPR）显著升高（t>2.988，P<0.01）。PBD2、4、5时，S组MPR较N组显著降低（t=2.311，P<0.05；t=3.054、3.319，P<0.01），平均值分别为3.17、2.33、1.75 nmol/湿重g/3 h。N组和S组之间未观察到显著变化。
休克期切痂植皮可减轻骨骼肌的高蛋白分解代谢，对机体有益。
