全身低温对吸入性损伤大鼠肺的保护作用

Protection of Whole-body Hypothermia for Lungs of Rats with Inhalation Injury

目的观察全身低温对烟雾吸入性损伤大鼠的急性肺部损伤的影响。方法将54只健康雄性SD大鼠随机分为3组,正常对照组、单纯致伤组、全身低温组,每组18只。单纯致伤组致伤后放恒温水浴箱中,维持正常体温。全身低温组致伤后作全身低温处理维持(33±0.5)℃持续1 h后升为正常体温。正常对照组不致伤。3组大鼠于伤后6 h后取腹主动脉血2 mL离心取血清,检测肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)的含量。取右下肺行病理切片,左肺作肺组织湿干重比。结果单纯致伤组和全身低温组与正常对照组相比烟雾吸入性损伤6 h后肺组织湿干重比显著升高(P<0.05),腹主动脉血中TNFα-、IL-6的含量显著升高(P<0.05),肺部充血水肿及炎症细胞浸润程度严重。全身低温组与单纯致伤组相比肺组织湿干重比降低(P<0.05),腹主动脉血中TNF-α、IL-6的含量降低(P<0.05),肺部充血水肿及炎症细胞浸润程度减轻。结论全身低温可以减轻烟雾吸入性损伤大鼠的急性肺部炎症、减轻肺损伤。

Objective To observe the effects of whole-body hypothermia on acute lung injury in rats that have suffered smoke inhalation injury. Methods 54 healthy male SD rats were divided into 3 groups at random with 18 in each group： the normal control group,the simple inhalation injury group and the whole-body hypothermia group.Rats in the simple inhalation injury group were put into a thermostat water bathtub to maintain normothermia after they were injured.After being injured,rats in the whole-body hypothermia group were kept under hypothermic conditions（33±0.5）℃ for 1 h before their body temperature was raised to normothermia.Rats in the normal control group were not injured.6h after smoke inhalation injury,2ml of blood of abdominal aorta was collected from each rat in the 3 groups and centrifuged to obtain serum albumin in which the contents of tumor necrosis factor-α（TNF-α） and interleukin-6（IL-6） were measured.The right lower lungs were excised for pathological section,and the left lungs for measurement of wet-to-dry weight ratio of lung tissues. Results Compared with the normal control group,6 h after smoke inhalation injury in both the simple inhalation injury group and the whole-body hypothermia group,the wet-to-dry weight ratio of lung tissues rose remarkably（P〈0.05）,the contents of TNF-α and IL-6 in the blood of abdominal aorta increased substantially（P〈0.05）,and pulmonary edema and congestion and inflammatory cells infiltration were serious.Compared with the simple inhalation injury group,in the whole-body hypothermia group,the wet-to-dry weight ratio of lung tissues declined（P〈0.05）,the contents of TNF-α and IL-6 in the blood of abdominal aorta decreased（P〈0.05）,and the severity of pulmonary edema and congestion and inflammatory cells infiltration was alleviated. Conclusion Whole-body hypothermia can alleviate the acute pulmonary inflammation in rats with smoke inhalation injury and therefore mitigate lung injury.