Abribat T, Brazeau P, Davignon I, Garrel D R
Neuroendocrinology Laboratory, Notre-Dame Hospital Research Center, Montreal, Quebec, Canada.
Clin Endocrinol (Oxf). 1993 Nov;39(5):583-9. doi: 10.1111/j.1365-2265.1993.tb02413.x.
Insulin-like growth factor-I (IGF-I) is a polypeptide growth factor that stimulates protein synthesis. The aims of this study were to determine (1) the effect of a severe burn on blood IGF-I levels and (2) the variables controlling IGF-I level variations during recovery of these hypermetabolic patients.
Eleven patients, nine men and two women (age range 22-55 years) were studied for 25 days following a severe burn (18-75% of total body surface area, mean 36%). Nitrogen balances were recorded daily and total IGF-I levels were measured every 3 days.
IGF-I was extracted from serum using a validated formic acid-acetone methodology, then measured by a double antibody radioimmunoassay. IGF-I levels were compared to those of a reference healthy population.
Within 24 hours following injury, IGF-I levels were low in all patients when compared to normal values for the same age range (mean +/- SEM of all patients, 131 +/- 26 micrograms/l). They remained low for the first week (days 4 and 7, 109 +/- 16 micrograms/l), then increased to reach normal values at the end of the study period (days 10-16, 144 +/- 19 micrograms/l, P = 0.005 when compared to days 4-7; days 19-25, 206 +/- 30 micrograms/l, P = 0.008 when compared to days 10-16). IGF-I levels were negatively correlated with age in the second phase of recovery only (days 10-16, r = -0.70, P < 0.05; days 19-25, r = -0.75, P < 0.01) and with severity of burn between days 19 and 25 (r = -0.62, P < 0.05). The presence of bronchial burn injury tended to lower IGF-I blood concentration (P = 0.08). Whereas IGF-I concentrations increased in the later phase of recovery, nitrogen balances did not. As a result, there was no significant correlation between these parameters.
IGF-I levels followed a biphasic pattern in severely burned patients. They dropped dramatically in response to the traumatic shock, then increased during recovery. The degree of increase was dependent on the age of the patient and on the severity of the burn, but was not associated with an improvement in the nitrogen balance.
胰岛素样生长因子-I（IGF-I）是一种刺激蛋白质合成的多肽生长因子。本研究的目的是确定：（1）严重烧伤对血液中IGF-I水平的影响；（2）这些高代谢患者恢复过程中控制IGF-I水平变化的变量。
11例患者，9名男性和2名女性（年龄范围22 - 55岁），在严重烧伤（占体表面积的18 - 75%，平均36%）后接受了25天的研究。每天记录氮平衡，每3天测量一次总IGF-I水平。
采用经验证的甲酸 - 丙酮方法从血清中提取IGF-I，然后通过双抗体放射免疫测定法进行测量。将IGF-I水平与参考健康人群的水平进行比较。
受伤后24小时内，与同年龄范围的正常值相比，所有患者的IGF-I水平均较低（所有患者的平均值±标准误，131±26微克/升）。在第一周内仍保持较低水平（第4天和第7天，109±16微克/升），然后在研究期结束时升高至正常值（第10 - 16天，144±19微克/升，与第4 - 7天相比，P = 0.005；第19 - 25天，206±30微克/升，与第10 - 16天相比，P = 0.008）。仅在恢复的第二阶段，IGF-I水平与年龄呈负相关（第10 - 16天，r = -0.70，P < 0.05；第19 - 25天，r = -0.75，P < 0.01），且在第19至25天与烧伤严重程度呈负相关（r = -0.62，P < 0.05）。存在支气管烧伤损伤倾向于降低IGF-I血液浓度（P = 0.08）。尽管在恢复后期IGF-I浓度升高，但氮平衡并未改善。因此，这些参数之间无显著相关性。
严重烧伤患者的IGF-I水平呈双相模式。在创伤性休克后急剧下降，然后在恢复过程中升高。升高程度取决于患者年龄和烧伤严重程度，但与氮平衡的改善无关。
