Mermel V L, Wolfe B M, Hansen R J, Clifford A J
Department of Physiological Sciences, School of Veterinary Medicine, University of California, Davis 95616.
JPEN J Parenter Enteral Nutr. 1991 Mar-Apr;15(2):128-36. doi: 10.1177/0148607191015002128.
A modified intraperitoneal pool flooding technique, employing L-3H-tyrosine, was developed for measuring muscle protein synthetic rates following traumatic injury. Sufficient radiolabeled tyrosine was injected intraperitoneally to effect a six-fold increase in plasma tyrosine concentration (124-800 microM) resulting in constant, sustained specific radioactivities in plasma- and intracellular-free tyrosine pools. Localized vs systemic effects of thermal and surgical trauma on gastrocnemius muscle protein turnover were assessed 2 and 4 days postinjury. Thermal trauma increased total, myofibrillar, and sarcoplasmic muscle protein synthesis (44%) and protein degradation (300%). Conversely, surgical trauma decreased synthesis of total (24%), myofibrillar (14%), and sarcoplasmic (43%) muscle proteins without altering protein degradation. Short-term restriction of pair-fed controls did not affect either aspect of protein turnover.
为了测量创伤后肌肉蛋白质合成率，开发了一种改良的腹腔内灌注技术，该技术使用L-3H-酪氨酸。腹腔内注射足够的放射性标记酪氨酸，使血浆酪氨酸浓度增加六倍（124 - 800微摩尔），从而使血浆和细胞内游离酪氨酸池中的比放射性保持恒定且持续。在损伤后2天和4天评估热损伤和手术创伤对腓肠肌蛋白质周转的局部和全身影响。热损伤增加了总肌肉蛋白、肌原纤维蛋白和肌浆蛋白的合成（44%）以及蛋白质降解（300%）。相反，手术创伤降低了总肌肉蛋白（24%）、肌原纤维蛋白（14%）和肌浆蛋白（43%）的合成，而不改变蛋白质降解。对成对喂养的对照组进行短期限制，对蛋白质周转的任何一个方面都没有影响。
