生长激素对严重烧伤患者支链氨基酸代谢的影响

The effects of recombinant human growth hormone on the metabolism of branch chain amino acid in severely burned patients

目的 探讨严重烧伤患者手术后应用重组人生长激素 (rhGH)对支链氨基酸代谢的影响及可能的机制。 方法 选择 1999年 1月～ 2 0 0 1年 1月间 ,烧伤总面积大于 30 %、Ⅲ度面积大于10 %TBSA、年龄 12～ 5 0岁的重度烧伤患者 5 0例 ,分为rhGH治疗组和对照组。伤后 3d内切痂植皮 ,rhGH组从术后第 1天开始每晚皮下注射rhGH(0 .3U/kg) ,共 10d。分别于术前、术后 1、3、7、10、14d清晨抽取两组患者静脉血 ,观察生长激素 (GH)、支链氨基酸指标和患者尿 3 甲基组氨酸 (3 MH)水平的变化。 结果 两组患者术前血清GH浓度较正常值显著降低 (P <0 0 5 ) ,术后 3d起rhGH组血清GH浓度较对照组显著增高 (P <0 0 5 )。尿 3 MH的排出量均有增加 ,但对照组显著高于rhGH组 (P <0 0 5 )。患者血浆支链氨基酸水平术前及术后第 1天低于正常值 ,rhGH组术后第 3天、对照组术后第 7天 ,血浆缬氨酸、异亮氨酸、亮氨酸水平升高 ,分别达峰值 ,之后逐渐降低 ,自术后第 7天开始rhGH组血浆支链氨基酸水平显著低于对照组 (P <0 .0 5 )。rhGH组血中GH浓度与尿3 MH排出量之间呈显著负相关 (P <0 .0 1)。 结论 大面积烧伤患者术后应用rhGH ,可促进骨骼肌摄取氨基酸 ,合成蛋白质 ,降低肌肉蛋白分解速率。

Objective To explore the effects of recombinant human growth hormone (rhGH) when applied postoperatively on the metabolism of branch chain amino acid in severely burned patients. Methods Fifty burn patients, aged 12 50 years and inflicted by more than 30% TBSA with 10% or more of III degree burn and admitted from the January of 1999 to the January of 2001 were enrolled in the study. The patients were randomly divided into rhGH treating (rhGH group) and control groups. Escharectomy was performed within 3 postburn day (PBDs). rhGH (0.3 IU/kg) was injected percutaneously every evening for ten days since the 1st postoperative day (POD). The changes of the plasma levels of GH and branch chain amino acid and the urine level of 3 methyl histidine (3 MH) were observed in the morning in the patients from the two groups. Results The plasma GH level before operation decreased obviously in two groups of patients when comparing with normal value (P<0 05). The plasma GH level in rhGH group was evidently higher than that in control group since the 3rd POD (P<0.05). There was significant increase of the output amount of urine 3 MH in all patients, but which was obviously higher in control group than that in rhGH group (P<0 05). The plasma levels of branch chain amino acid in burn patients before and one day after operation were lower than normal levels. The plasma levels of valine, isoleucine and leucine increased to peak values at POD 3 in rhGH group and at POD 7 in control group and decreased thereafter. The plasma branch chain amino acid level in rhGH group was evidently lower than that in control group since POD 7 (P<0.05). The plasma GH level in rhGH group was negatively and significantly correlated with the urine output amount of 3 MH (P<0.01). Conclusion Postoperative application of rhGH in major burn patients might be beneficial to the protein synthesis from amino acids by skeletal muscles and to the decrease of muscle protein degradating rate. [