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目的:探讨不同小剂量甘精胰岛素对烫伤延迟复苏大鼠器官的抗氧化保护作用。方法:按随机数字表法将40只雄性SD大鼠分为假伤组、延迟复苏对照组及甘精胰岛素0.5、1.0、2.0 U组，每组8只。将大鼠浸入（95.0±0.5）℃热水中15 s制备30%总体表面积Ⅲ度烫伤模型；假伤组大鼠浸入37 ℃水浴锅中15 s模拟烫伤。甘精胰岛素0.5、1.0、2.0 U组分别于大鼠烫伤后2 h皮下注射甘精胰岛素0.5、1.0、2.0 U·kg -1·d -1，延迟复苏对照组同法注射等量生理盐水；各组于伤后6 h腹腔注射生理盐水40 mL/kg复苏大鼠。假伤组模拟烫伤后即刻采集大鼠腹主动脉血及心脏、肾脏组织，其他4组于烫伤后24 h采集标本。采用分光光度法测定血糖、心肌酶〔乳酸脱氢酶（LDH）、肌酸激酶（CK）、α-羟丁酸脱氢酶（α-HBDH）、天冬氨酸转氨酶（AST）〕及肾功能指标〔血尿素氮（BUN）、血肌酐（SCr）〕，采用免疫抑制法测定肌酸激酶同工酶（CK-MB）活性，评估不同小剂量甘精胰岛素对烫伤延迟复苏大鼠血糖及心肾功能的影响；采用分光光度法检测大鼠心脏、肾脏组织氧化及抗氧化指标〔黄嘌呤氧化酶（XOD）、髓过氧化物酶（MPO）、铜锌超氧化物歧化酶（CuZn-SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GSH-Px）及总抗氧化能力（T-AOC）〕，分析不同小剂量甘精胰岛素干预后的抗氧化效应。 结果:与假伤组比较，延迟复苏对照组大鼠血糖显著升高，心肾功能明显降低，氧化能力增强，抗氧化能力下降。给予甘精胰岛素干预后，随着甘精胰岛素剂量增加，大鼠血糖、心肌酶及肾功能指标均呈逐渐下降趋势，氧化指标持续降低，抗氧化指标持续升高，当剂量为2.0 U·kg -1·d -1时，血糖、LDH、CK、CK-MB、α-HBDH、AST、BUN、SCr、XOD及MPO均显著低于延迟复苏对照组〔血糖（mmol/L）：5.91±0.25比11.76±0.36，LDH（U/L）：3 332.12±51.61比5 008.94±490.12，CK（kU/L）：0.49±0.03比0.85±0.04，CK-MB（U/L）：125.40±12.19比267.52±11.63，α-HBDH（U/L）：122.99±5.37比240.85±13.99，AST（U/L）：11.95±1.81比17.87±1.57，BUN（mmol/L）：4.72±0.15比7.16±0.34，SCr（μmol/L）：87.11±6.51比137.50±11.36，XOD（U/g）：心脏组织为166.29±3.27比204.90±4.82、肾脏组织为63.51±1.46比79.69±1.75，MPO（U/g）：心脏组织为1.05±0.02比1.55±0.06、肾脏组织为1.04±0.04比1.87±0.01，均 P<0.05〕，CuZn-SOD、CAT、GSH-Px及T-AOC均显著高延迟复苏对照组〔CuZn-SOD（kU/g）：心脏组织为82.95±2.69比56.52±2.26、肾脏组织为94.50±2.73比62.02±1.66，CAT（U/g）：心脏组织为36.07±2.01比15.15±2.22、肾脏组织为184.49±4.53比156.02±3.96，GSH-Px（kU/g）：心脏组织为231.93±8.03比179.48±3.15、肾脏组织为239.63±7.30比172.20±2.09，T-AOC（kU/g）：心脏组织为4.85±0.23比2.71±0.11、肾脏组织为5.51±0.08比3.50±0.07，均 P<0.05〕。 结论:不同小剂量甘精胰岛素（≤2.0 U·kg -1·d -1）均可对烫伤延迟复苏大鼠心脏、肾脏发挥抗氧化保护效应，且呈现剂量依赖关系。

Objective:To study the antioxidant protective effects of different low-dose of insulin glargine on organs of burned rats with delayed resuscitation.Methods:Forty male Sprague-Dawley (SD) rats were randomly divided into sham group, delayed resuscitation control group, and insulin glargine 0.5, 1.0, and 2.0 U groups, with 8 rats in each group. The rats were immersed in hot water (95.0±0.5) ℃ for 15 s to establish the third-degree scald model with 30% total body surface area. The rats in the sham group were immersed in a 37 ℃ water bath for 15 s. Insulin glargine (0.5, 1.0, 2.0 U·kg -1·d -1) was injected subcutaneously in corresponding insulin glargine group 2 hours after injury, and the same amount of normal saline was injected intraperitoneally in the delayed resuscitation control group. Intraperitoneal injection of normal saline 40 mL/kg simulated delayed resuscitation 6 hours after injury in all groups. Abdominal aortic blood samples, heart and kidney tissue were collected immediately after simulating burn in the sham group, and 24 hours after burn in other four groups. The blood glucose, myocardial enzymes [lactate dehydrogenase (LDH), creatine kinase (CK), α-hydroxybutyrate dehydrogenase (α-HBDH), and aspartate aminotransferase (AST)] and renal function indexes [blood urea nitrogen (BUN) and serum creatinine (SCr)] were measured by spectrophotometry, and the isoenzyme MB of creatine kinase (CK-MB) level was determined by immunosuppression method to evaluate the effects of different low-dose insulin glargine intervention on blood glucose, cardiac and renal functions in scalded rats with delayed resuscitation. The oxidative and antioxidant indices [xanthine oxidase (XOD), myeloperoxidase (MPO), copper-zinc superoxide dismutase (CuZn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and total antioxidant capacity (T-AOC)] from the heart and kidney tissues of rats were detected by spectrophotometry to analyze the antioxidant effects of different low-dose insulin glargine interventions. Results:Compared with the sham group, the blood glucose of the rats in the delayed resuscitation control group was significantly increased, the heart and kidney functions were significantly reduced, the oxidation capacity was enhanced, and the antioxidant indicators were significantly reduced. After the intervention of insulin glargine, with the increase of insulin glargine dose, the blood glucose, myocardial enzyme and renal function indicators of rats showed a gradual downward trend, the oxidation indicators continued to decrease, and the antioxidant indicators showed a gradual upward trend. When the dose was 2.0 U·kg -1·d -1, the blood glucose, LDH, CK, CK-MB, α-HBDH, AST, BUN, SCr, XOD and MPO were significantly lower than those in the delayed resuscitation control group [blood glucose (mmol/L): 5.91±0.25 vs. 11.76±0.36, LDH (U/L): 3 332.12±51.61 vs. 5 008.94±490.12, CK (kU/L): 0.49±0.03 vs. 0.85±0.04, CK-MB (U/L): 125.40±12.19 vs. 267.52±11.63, α-HBDH (U/L): 122.99±5.37 vs. 240.85±13.99, AST (U/L): 11.95±1.81 vs. 17.87±1.57, BUN (mmol/L): 4.72±0.15 vs. 7.16±0.34, SCr (μmol/L): 87.11±6.51 vs. 137.50±11.36, XOD (U/g): 166.29±3.27 vs. 204.90±4.82 in heart tissue, 63.51±1.46 vs. 79.69±1.75 in kidney tissue, MPO (U/g): 1.05±0.02 vs. 1.55±0.06 in heart tissue, 1.04±0.04 vs. 1.87±0.01 in kidney tissue, all P < 0.05], and CuZn-SOD, CAT, GSH-Px and T-AOC were significantly higher than those in the delayed resuscitation control group [CuZn-SOD (kU/g): 82.95±2.69 vs. 56.52±2.26 in heart tissue, 94.50±2.73 vs. 62.02±1.66 in kidney tissue, CAT (U/g): 36.07±2.01 vs. 15.15±2.22 in heart tissue, 184.49±4.53 vs. 156.02±3.96 in kidney tissue, GSH-Px (kU/g): 231.93±8.03 vs. 179.48±3.15 in heart tissue, 239.63±7.30 vs. 172.20±2.09 in kidney tissue, T-AOC (kU/g): 4.85±0.23 vs. 2.71±0.11 in heart tissue, 5.51±0.08 vs. 3.50±0.07 in kidney tissue, all P < 0.05]. Conclusion:Different low-dose of insulin glargine (≤2.0 U·kg -1·d -1) could exert antioxidant protection on the heart and kidney of rats with delayed resuscitation after burns, with a dose-dependent manner.