Karner J, Roth E, Funovics J, Hanusch J, Walzer L, Adamiker D, Berger A, Meissl G
Burns Incl Therm Inj. 1984 Dec;11(2):130-7. doi: 10.1016/0305-4179(84)90136-0.
In this study the influence of a severe catabolic situation (scalding and nitrogen deprivation) on amino acid (AA) metabolism was investigated in an experimental rat model. Scalding of 25 per cent of the total body surface area (TBSA) and hypocaloric alimentation (5.6 kcal per 100 g rat per day, no nitrogen) resulted in mean daily nitrogen losses of -0.27 +/- 0.3 g. Compared to anabolic growing rats this nitrogen catabolism significantly reduced the total free AA content of muscle (-47 per cent, P less than 0.001) and liver (-39 per cent, P less than 0.001). The total plasma AA concentrations were slightly increased in catabolic rats (+10 per cent). In catabolic rats muscle glycine concentrations dropped significantly (-79 per cent, P less than 0.001), while glutamine concentrations decreased by 22 per cent, which was not significant. Branched chain AA and phenylalanine were significantly elevated both in muscle and in plasma. Scalding and nitrogen depletion in rats leads to characteristic changes in plasma, muscle and liver AA concentrations, which are comparable to the results obtained in catabolic patients. However, the low muscle glycine concentrations in burned rats differ from the clinical observations where glutamine rather than glycine concentrations in muscle tissue are reduced. The rat model seems to be well suited for studying the influence of various therapeutic approaches such as different forms of parenteral nutrition or hormonal substitution on nitrogen catabolism.
在本研究中，我们在实验大鼠模型中研究了严重分解代谢状态（烫伤和氮剥夺）对氨基酸（AA）代谢的影响。烫伤大鼠全身表面积（TBSA）的25%并给予低热量营养（每100克大鼠每天5.6千卡，不含氮），导致平均每日氮损失为-0.27±0.3克。与处于合成代谢生长状态的大鼠相比，这种氮分解代谢显著降低了肌肉中总游离AA含量（-47%，P<0.001）和肝脏中总游离AA含量（-39%，P<0.001）。分解代谢大鼠的血浆总AA浓度略有升高（+10%）。在分解代谢大鼠中，肌肉甘氨酸浓度显著下降（-79%，P<0.001），而谷氨酰胺浓度下降了22%，但差异不显著。支链氨基酸和苯丙氨酸在肌肉和血浆中均显著升高。大鼠的烫伤和氮耗竭导致血浆、肌肉和肝脏AA浓度发生特征性变化，这与在分解代谢患者中获得的结果相似。然而，烧伤大鼠肌肉中甘氨酸浓度较低与临床观察结果不同，临床观察发现肌肉组织中谷氨酰胺而非甘氨酸浓度降低。大鼠模型似乎非常适合研究各种治疗方法（如不同形式的肠外营养或激素替代）对氮分解代谢的影响。
