Koea J B, Douglas R G, Shaw J H, Gluckman P D
Department of Surgery, University of Auckland, New Zealand.
Br J Surg. 1993 Jun;80(6):740-4. doi: 10.1002/bjs.1800800627.
The effect of 7 days of subcutaneously administered bovine growth hormone (bGH) (0.2 mg kg-1 day-1; n = 4) or an equivalent volume of 0.15 mol l-1 saline (n = 3) on protein metabolism was assessed in lambs. The catabolic response to 48 h of starvation and subsequent hypocaloric total parenteral nutrition (TPN) was measured using primed constant intravenous infusions of [15N]urea and [14C]leucine. Following 48 h of starvation and 7 h of TPN, bGH-treated animals had a significantly decreased rate of net protein catabolism compared with controls (mean(s.e.m.) 2.4(0.2) versus 3.2(0.3) g kg-1 day-1, P < 0.01). The mean(s.e.m.) rate of whole-body protein catabolism was also significantly decreased in bGH-treated animals at 10.9(0.3) g kg-1 day-1 compared with 12.9(0.7) g kg-1 day-1 in saline-treated controls (P < 0.05). In addition, the rates of net and whole-body protein catabolism decreased significantly (P < 0.05) during the period of hypocaloric parenteral feeding to mean(s.e.m.) values of 2.3(0.2) and 8.6(0.6) g kg-1 day-1 respectively in bGH-treated animals. By contrast, in saline-treated controls net and whole-body protein catabolism continued to increase during hypocaloric parenteral feeding. There was a significant decrease (P < 0.05) in the rate of [14C]leucine uptake in tissues of the gastrointestinal tract, heart and diaphragm in bGH-treated animals compared with controls. These results demonstrate that daily administration of growth hormone decreases the catabolic response to a metabolic stress, resulting in the conservation of protein in the heart, diaphragm, gastrointestinal tract and musculoskeletal system by a primary anticatabolic action. In addition, growth hormone therapy initiated before induction of the catabolic state enhances the protein-sparing effects of TPN. Further study is justified to determine whether growth hormone therapy initiated before elective or urgent surgery in the nutritionally depleted patient may have a role in reducing the severity of the postoperative catabolic state, particularly in the patient in whom a complicated course is anticipated.
评估了皮下注射7天牛生长激素（bGH）（0.2毫克/千克/天；n = 4）或等体积0.15摩尔/升生理盐水（n = 3）对羔羊蛋白质代谢的影响。使用[15N]尿素和[14C]亮氨酸的预充式持续静脉输注来测量对48小时饥饿及随后低热量全胃肠外营养（TPN）的分解代谢反应。在饥饿48小时和TPN 7小时后，与对照组相比，bGH治疗的动物净蛋白分解代谢率显著降低（平均值（标准误）2.4（0.2）对3.2（0.3）克/千克/天，P < 0.01）。与生理盐水治疗的对照组（12.9（0.7）克/千克/天）相比，bGH治疗的动物全身蛋白分解代谢的平均值（标准误）率也显著降低，为10.9（0.3）克/千克/天（P < 0.05）。此外，在低热量肠外喂养期间，bGH治疗的动物净蛋白和全身蛋白分解代谢率显著降低（P < 0.05），分别降至平均值（标准误）2.3（0.2）和8.6（0.6）克/千克/天。相比之下，在生理盐水治疗的对照组中，低热量肠外喂养期间净蛋白和全身蛋白分解代谢持续增加。与对照组相比，bGH治疗的动物胃肠道、心脏和膈肌组织中[14C]亮氨酸摄取率显著降低（P < 0.05）。这些结果表明，每日给予生长激素可降低对代谢应激的分解代谢反应，通过主要的抗分解代谢作用，使心脏、膈肌、胃肠道和肌肉骨骼系统中的蛋白质得以保存。此外，在分解代谢状态诱导前开始的生长激素治疗可增强TPN的蛋白质节省作用。有理由进行进一步研究，以确定在营养耗竭的患者进行择期或急诊手术前开始生长激素治疗是否可能在减轻术后分解代谢状态的严重程度方面发挥作用，特别是在预计病程复杂的患者中。
