Lopes J, Russell D M, Whitwell J, Jeejeebhoy K N
Am J Clin Nutr. 1982 Oct;36(4):602-10. doi: 10.1093/ajcn/36.4.602.
Skeletal muscle function was studied in 10 malnourished patients with various gastrointestinal disorders and in 22 normal subjects. The function of the adductor pollicis muscle was assessed by electrical stimulation of the ulnar nerve. The objective parameters of muscle function measured were: 1) Force of contraction expressed as a percentage of the maximal force obtained with electrical stimulation at 10, 20, 30, 50 and 100 Hz. 2) Maximal relaxation rate expressed as percentage force loss/!10 ms. 3) Endurance expressed as percentage force loss/30 s. The force of contraction at 10 Hz was higher in malnourished patients compared with normal subjects, with a mean +/- SEM (n) of 43.0 +/- 4.2% (n = 10) and 28.8 +/- 1.2% (n = 22), respectively, (p less than 0.001). The maximal relaxation rate was slower in patients compared with normals with a mean +/- SEM (n) of 7.2 +/- 0.4% (n = 9) ad 9.6 +/- 0.2% (n = 22), respectively, (p less than 0.001). Muscle endurance testing showed an increased force loss with prolonged tetanic stimulation in patients compared with normals, with a mean +/- SEM (n) of 29.1 +/- 4.0% (n = 7) and 3.5 +/- 0.8% (n = 22), respectively, (p less than 0.001). Four patients were restudied after a 4-wk period of total parenteral nutrition, with a significant improvement in muscle function parameters. Malnutrition results in both increased muscle fatiguability and an altered pattern of muscle contraction and relaxation which are reversible by nutritional supplementation. This technique promises to be valuable in assessing the functional effects of malnutrition and the response to nutritional support.
对10名患有各种胃肠道疾病的营养不良患者和22名正常受试者的骨骼肌功能进行了研究。通过对尺神经进行电刺激来评估拇内收肌的功能。所测量的肌肉功能客观参数包括：1）收缩力，以在10、20、30、50和100赫兹电刺激下获得的最大力的百分比表示。2）最大松弛率，以每10毫秒的力损失百分比表示。3）耐力，以每30秒的力损失百分比表示。与正常受试者相比，营养不良患者在10赫兹时的收缩力更高，其平均值±标准误（n）分别为43.0±4.2%（n = 10）和28.8±1.2%（n = 22），（p < 0.001）。与正常人相比，患者的最大松弛率较慢，其平均值±标准误（n）分别为7.2±0.4%（n = 9）和9.6±0.2%（n = 22），（p < 0.001）。肌肉耐力测试显示，与正常人相比，患者在长时间强直刺激下力损失增加，其平均值±标准误（n）分别为29.1±4.0%（n = 7）和3.5±0.8%（n = 22），（p < 0.001）。4名患者在接受4周的全胃肠外营养后再次接受研究，肌肉功能参数有显著改善。营养不良导致肌肉易疲劳性增加以及肌肉收缩和松弛模式改变，而营养补充可使其逆转。该技术有望在评估营养不良的功能影响以及对营养支持的反应方面具有重要价值。
