乳化七氟烷预处理对大鼠肝脏缺血再灌注损伤的保护作用

Protective effect of emulsified sevoflurane preconditioning on ischemia reperfusion injury in rat liver

目的研究乳化七氟烷预处理对大鼠肝脏缺血再灌注损伤的保护作用。方法将40只健康雄性Sprague-Dawley大鼠随机分为假手术组(S组,6只)、缺血再灌注组(IR组,10只)、20%脂肪乳预处理组(FAT组,12只)和乳化七氟烷组(SEVO组,12只)。S组大鼠开腹后以温的0.9%氯化钠溶液纱布覆盖切口,1h后关腹。IR组大鼠开腹后予无损伤血管夹阻断左肝叶和中肝叶的门静脉及肝动脉血供,以温的0.9%氯化钠溶液纱布覆盖切口,持续1h后移去血管夹并关腹。FAT组和SEVO组大鼠麻醉后分别经微量静脉输液泵输注20%脂肪乳和体积分数为0.036的乳化七氟烷(均为10mL·kg-1·h-1),30min后开腹建立肝脏热缺血再灌注模型,具体操作同IR组。大鼠均在4h后处死。观察各组大鼠肝组织病理改变,并检测血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、肿瘤坏死因子(TNF)-α、白细胞介素(IL)-1、IL-10水平。结果 IR组、FAT组和SEVO组大鼠的血清ALT、AST、TNF-α、IL-1和IL-10水平均显著高于S组(P值均<0.05)。SEVO组大鼠的血清ALT、AST、TNF-α和IL-1水平均显著低于IR组(P值均<0.05),IL-10水平显著高于S组(P<0.05)。IR组与FAT组间上述指标的差异均无统计学意义(P值均>0.05)。病理检查示,IR组和FAT组可见小叶中央肝细胞呈空泡样变性并聚集成簇,大量肝细胞细胞核浓缩并深染,呈坏死前改变,部分肝细胞坏死,肝血窦及小叶中央重度充血肿胀;SEVO组肝小叶结构尚存,肝细胞轻度水肿,小叶中央个别肝细胞呈坏死前改变,部分肝血窦狭窄,门管区少量炎性细胞浸润,肝细胞损伤程度较IR组轻。结论乳化七氟烷预处理对大鼠肝脏热缺血再灌注损伤具有保护作用,ALT和AST水平明显下降,肝细胞损伤减轻,其机制可能与抑制炎性细胞因子生成及促进抗炎细胞因子表达有关。

Objective To investigate the protective effect of emulsified sevoflurane preconditioning on rat liver ischemia-reperfusion （IR） injury. Methods Forty healthy male Sprague-Dawley rats were randomly divided into 4 groups. The rats in sham-operation group （S, n = 6） ungerwent midline laparotomy, and the incision was covered with 0.9% warm saline gauze and closed 1 h later. The inflow for the left and middle lobe, including branch of portal vein and hepatic artery in ischemia reperfusion group （IR, n = 10）, was occluded by atraumatic microvascular clamp. The clamp was removed and the incision was closed 1 h later. Fat emulsion group （.FAT, n = 12） and emulsified sevoflurane group （SEVO, n = 12） ： After rats were anesthetized, 20% intralipid and 3.6% （v/v） emulsified sevoflurane were respectively infused through microinfusion pump at the rate of 10 mL. kg^-1. h^-1 for 30 min prior to IR. The other procedures were the same as IR group. All the rats were executed 4 h later. Pathological changes of liver were observed in each group. Serum alanine aminotransferase （ALT）, aspartate aminotransferase （AST）, tumor necrosis factor-α（TNF-α）, interleukin （IL）-1, and IL-10 were determined. Results ALT, AST, TNF-α, IL-1 and IL-10 were significantly higher in groups IR, FAT and SEVO than in group S （all P〈0.05）. ALT, AST, TNF-α and IL-1 were significantly lower in group SEVO than in group IR（all P〈0.05）, while IL-10 in group SEVO was significantly higher than in group S （P〈0.05）. There were no statistical differences in the parameters between group IR and group FAT （all P〈0.05）. Massive neutrophils accumulation and a lot of congestion, vacuolization, and necrosis were found in groups IR and FAT. There were less neutrophil accumulation and very limited congestion, vacuolization, and necrosis in group SEVO. The injury of hepatocytes was milder in group SEVO than in group IR. Conclusion Emulsified sevoflurane preconditioning can reduce the ischemia reperfusion injury of rat liver. The levels of ALT and AST and the injury of hepatocytes are remarkably decreased after the preconditioning. The protective mechanism may be related to the reduced expression of inflammative cytokines and elevated expression of anti-inflammation cytokines.