不同浓度异氟醚对大鼠肺脏的影响

目的 观察吸入不同浓度异氟醚诱发大鼠急性肺损伤的作用。方法 90只Wistar大鼠随机分为三组,每组30只正常对照组(C组)、0.6％异氟醚吸入组(0.6％Iso组)和1.4％异氟醚吸人组(1.4％Iso组)。每组分别在吸入异氟醚2、4和8h处死10只大鼠。检测支气管肺泡灌洗液中中性粒细胞比值及蛋白浓度、肺含水量,用Western blot检测支气管肺泡灌洗液及血清中表面活性蛋白A(SP-A)的含量;光镜下观察肺组织病理形态的改变。结果 三组大鼠吸入异氟醚后各时点肺含水量差异无显著性(P>0.05)。1.4％lso组在吸入异氟醚后8 hBALF中蛋白浓度、中性粒细胞比值均高于C组和0.6％Iso组(P<0.05)。与C组比较,1.4％Iso组大鼠吸入异氟醚后8 h BALF中SP-A浓度降低,而血清中SP-A浓度升高(P<0.05或0.01)。1.4％Iso组大鼠在吸入异氟醚后8 h肺毛细胞血管轻度扩张、充血、水肿,部分肺泡内中性粒细胞浸润。结论 长时间(8 h)吸入临床相关浓度的异氟醚可减弱肺泡上皮功能,其作用与吸入浓度和时间有关。

Effects of different concentratons of isoflurane on the lungs in rats

Objective It has been shown that fluorinated inhalational anesthetics have various adverse effects on the lungs. The aim of this study was to investigate the effects of different concentrations of isoflurane (ISO) on the lungs in rats.Methods Ninety Wistar rats of both sexes weighing 140-200 g were randomly divided into two groups : (A) control group received only oxygen inhalation ( n = 30) and (B) isoflurane group (n = 60) which was farther divided into 2 subgroups (n = 30):0.6% and 1.4% isoflurane. In each subgroup isoflurane was inhaled for 2 h ( n = 10), 4h (n = 10) or 8 h ( n = 10) . The animals were placed in a glass container and isoflurane was delivered from ISO vaporizer into the container through the inlet. The end-tidal ISO concentration was checked at the outlet. The animals were sacrificed at the end of ISO inhalation. The lungs were immediately removed and blood was collected for determination of (1) lung water content, (2) protein content and neutrophil ratio in broncho-alveolar lavage fluid (BALF) , (3) serum and BALF surfactant protein-A (SP-A) content and (4) microscopic examination. Results There was no significant difference in all variables between control group and 0.6% ISO subgroup. Exposure to 1.4% ISO for 8 h caused an increase in neutrophil ratio and protein content in BALF, and serum SP-A content but a decrease in BALF SP-A content. There was no significant difference in lung water content between control group and 1.4% ISO (8 h) subgroup. Conclusion Isoflurane (1 MAC) inhalation over 8 h may impair the function of alveolar epithelium.