不同浓度七氟醚预处理对内毒素性 急性肺损伤大鼠肺组织的影响

目的：比较3种不同浓度(3.6%,2.4%和1.2%)七氟醚预处理对内毒素性急性肺损伤大鼠肺组织的影响。方法：健康雄性SD大鼠36只，随机分为6组（n=6）：对照组（A组）、单纯七氟醚吸入组（B组）、3.6%七氟醚预处理组（C组）、2.4%七氟醚预处理组（D组）、1.2%七氟醚预处理组（E组）、内毒素组（F组）。分别在给药后（LPS或生理盐水）6 h 处死大鼠, 观察肺组织病理学结果，测定肺组织湿干比(W/ D)、髓过氧化物酶(MPO)活性及肺组织ICAM-1mRNA的表达。结果：与对照组比较，F组和不同浓度七氟醚预处理组肺组织病理损伤加重，肺W/D、MPO活性、ICAM-1mRNA表达升高(P＜0.05)。与F组比较，C组肺组织病理损伤减轻，MPO活性和ICAM-1mRNA表达降低(P＜0.05)，但肺W/D无明显降低（P＞0.05）；D组肺组织病理损伤减轻，肺W/D、MPO活性、ICAM-1mRNA表达均降低(P＜0.05)，F组肺组织MPO活性降低(P＜0.05)，但肺W/D和ICAM-1mRNA表达无明显降低（P＞0.05）。结论：2.4%七氟醚预处理可以减轻内毒素所致急性肺损伤,作用机制可能与其降低肺组织ICAM-1mRNA的表达上调，从而减少肺内中性粒细胞的浸润相关。

Effect of different concentrations of sevoflurane pretreatment on acute lung injury induced by endotoxin in rats

Objective To investigate the effect of 3 concentrations of sevoflurane pretreatment on acute lung injury induced by endotoxin in rats. Methods Thirty-six male SD rats were randomly divided into 6 groups:a control group(Group A), a sevoflurane group(Group B), a 3.6% sevoflurane pretreatment group(Group C), a 2.4% Sevoflurane pretreatment group(Group D), a 1.2% sevo sevoflurane pretreatment group(Group E), and lipopolysaccharide (Group F).The rats were killed 6 h after lipopolysaccharide (LPS) or saline injection.Histological examinations of the lung tissues were performed with light microscope. Lung wet/dry weight (W/D) ratio, myeloperoxidase (MPO) activity, and intercellular adhesion molecule 1 (ICAM-1) mRNA expression were assayed. Results Introvenous LPS significantly aggravated lung tissue damage,increased lung W/D ratio, MPO activity, and lung ICAM-1 mRNA expression compared with the control group(P＜0.05). Precondition with 2.4% sevoflurane significantly attenuated the above mentioned changes induced by LPS (P＜0.05). The 3.6% LPS (Group C) significantly attenuated lung tissue damage and decreased MPO activity,lung ICAM-1 mRNA expression compared with the Group F (P＜0.05),but no significant change in lung W/D ratio was seen (P＞0.05). MPO activity was significantly decreased in Group E (P＜0.05), but lung W/D ratio and lung ICAM- 1 mRNA expression had no significant changes (P＞0.05).Conclusion Precondition with 2.4% sevoflurane can reduce LPS induced lung injury in rats. Decreased expression of ICAM-1 and less accumulation of neutrophils were participated in its mechanism.