增加精氨酸摄入量对烧伤患者血浆氨基酸谱的影响

Influence of L-arginine supplementation on the plasma amino acid spectrum in burn patients

目的观察摄入大剂量精氨酸对烧伤患者血浆氨基酸谱的影响. 方法 10例烧伤患者随机分为烧伤试验组和烧伤对照组(各5例),前者给予占总热量2%的盐酸精氨酸静脉注射液,后者给予占总热量2%的14复合氨基酸静脉注射液.两组患者其他营养成分的摄入量均相同.营养方案自伤后第3天起执行,给予总量的1/4;伤后4、5 d给予总量的1/2;伤后6～21 d给予全量.在两组患者伤后3 d(方案实施前)及7、14、21、28 d清晨取其静脉血标本,检测血浆氨基酸谱水平.以10名健康志愿献血者的血浆氨基酸谱水平作为正常参考值. 结果伤后3 d,两组患者血浆瓜氨酸水平显著低于正常参考值(P<0.05),而鸟氨酸和精氨酸水平与正常参考值比较差异无统计学意义(P>0.05).烧伤对照组伤后3 d后精氨酸、瓜氨酸和鸟氨酸水平呈现下降趋势.而烧伤试验组伤后14、21、28 d血浆精氨酸水平分别为(280±121)、(223±106)、(110±44)μmol/L,与同期烧伤对照组(124±21)、(59±15)、(50±26)μmol/L相比明显偏高;伤后21 d瓜氨酸和鸟氨酸水平分别为(30±5)、(162±44)μmol/L,明显高于同期烧伤对照组(8±7)、(66±4)μmol/L(P<0.05或0.01).两组患者伤后血浆其他氨基酸水平差异均无统计学意义(P>0.05). 结论机体烧伤后血浆瓜氨酸转化为精氨酸的过程加速.增加外源性精氨酸摄入量可显著提高血浆精氨酸、鸟氨酸、瓜氨酸水平,但对其他氨基酸水平无明显影响,这一药理作用可能是通过加速鸟氨酸循环实现的.

Objective To explore the influence of L-arginine supplementation on the plasma amino acid spectrum in burn patients. Methods Ten burn patients were randomly divided into burn control （ n =5, with compound 14 amino acid injection accounting for 2% of the total caloric value） , and experimental （n = 5, with intravenous injection of L-arginine which accounted for 2% of total caloric value） groups. The intake of other nutrients for these two groups of patients was the same. The nutrient regimen was begun on the 3 PBD, with one quarter of the daily supply. On 4 and 5 PBD, one half of the daily supply was given,and from 6 to 21 PBD full supplementation was given. Venous blood samples were collected on 3, 7, 14, 21 and 28 PBD for the determination of plasma levels of amino acids. Ten normal volunteers served as normal control. Results The plasma level of citrulline in both groups was significantly lower than normal value （ P 〈 0.05 ）on 3 PBD before L-arginine supplementation. There was no obvious difference in plasma levelsof ornithine and arginine in the two groups on 3 PBD compared with normal value （ P 〉 0.05 ）. The plasma level of ornithine, citrulline and arginine in burn control group declined on 3 PBD. The plasma level of arginine in experimental group on 14 , 21 and 28 PBD were 280± 12μmol/L, 223 ±106μmol/L and 110±44μmol/L, respectively, which were significantly higher than those in burn control group （ 124 ± 21 μmol/L,59± 15 μmol/L,50 ± 26μmol/L）. The plasma level of ornithine （ 30± 5μmol/L） and citrulline （ 162 ± 44μmol/L） on 21 PBD in experimental group were markedly higher than those in burn control group （8 ± 7μmol/L, 66 ±4μmol/L, P 〈0.05 or 0.01 ）. There was no difference in the plasma levels of other amino acids at all postburn time points between the two groups （ P 〉 0.05 ）. Conclusion The production process of L-arginine from citrulline was accelerated after burns. The plasma levels of L-arginine, ornithine and citrulline were increased markedly after L-arginine supplementation, while that of other amino acids was not influenced. The pharmacological effects of L-arginine may be related to the promotion of ornithine cycle.