探讨阻断大鼠肝固有动脉建立肝缺血-再灌注损伤（IRI）模型的最佳灌注时间。

SD大鼠48只，平均体重（200±25）g，按随机数字表法随机分为IRI 0、1、3、6、12、24、48 h组和假手术（SO）组，每组各6只。IRI各组选择性阻断肝固有动脉1 h后血流恢复，分别在血流恢复0、1、3、6、12、24、48 h留取血和肝组织标本。SO组仅分离肝固有动脉，暴露第一肝门1 h后取相应标本。观察各组大鼠血清ALT、AST水平，肝组织病理学改变，肝组织DNA片段化率，肝组织Ki-67表达水平。多组计量资料的比较采用单因素方差分析和LSD-t检验。

IRI 0、1、3、6、12、24、48 h组和SO组大鼠血清ALT水平分别为（53±25）、（85±20）、（96±18）、（411±96）、（87±19）、（81±15）、（46±6）、（60±14）U/L。大鼠血清AST水平相应为（238±63）、（364±111）、（375±68）、（1 291±511）、（800±87）、（854±218）、（484±219）、（248±94）U/L。IRI 6 h组血清ALT、AST水平最高（F=36.015, 18.241；P<0.05）。IRI 6 h组肝组织损伤程度最重。大鼠肝组织DNA片段化率相应为（7.5±1.5）%、（9.2±2.2）%、（9.3±2.3）%、（12.6±2.4）%、（6.3±1.0）%、（5.4±0.9）%、（4.5±0.8）%、（4.5±1.1）%，6 h组肝组织DNA片段化率最高（F=15.992, P<0.05）。大鼠肝组织Ki-67表达相应为（3.5±1.4）、（5.6±1.8）、（8.7±2.3）、（13.7±2.4）、（15.2±1.2）、（20.5±2.2）、（31.8±2.5）、（2.4±1.2）个/高倍视野，IRI 48 h组肝组织Ki-67表达水平最高（F=261.707，P<0.05）。

阻断大鼠肝固有动脉可以成功建立肝IRI模型，IRI最佳灌注时间为6 h。

To investigate the optimum reperfusion duration of liver ischemia- reperfusion injury (IRI) model by occluding the proper hepatic artery in rats.

Fourty-eight Sprague Dawley (SD) rats with mean weight of (200±25) g were randomly assigned to 8 groups by random number table method: IRI- 0, 1, 3, 6, 12, 24, 48 h and sham operation (SO) group with 6 rats in each group. The proper hepatic arteries in rats of IRI groups were selectively occluded for 1 h and then blood flow recovered. Samples of blood and liver tissues were collected at the time points of 0, 1, 3, 6, 12, 24, 48 h of reperfusion. In SO group, samples were collected after the proper hepatic artery was isolated and the first portal was exposed for 1 h. The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), pathological changes, DNA fragmentation rates, and levels of Ki-67 expression of liver tissues were observed in each group. Measurement data of multiple groups were compared using one-way analysis of variance and LSD-t test.

The levels of serum ALT in IRI- 0, 1, 3, 6, 12, 24, 48 h and SO group were (53±25), (85±20), (96±18), (411±96), (87±19), (81±15), (46±6), (60±14) U/L respectively. The levels of serum AST were (238±63), (364±111), (375±68), (1 291±511), (800±87), (854±218), (484±219), (248±94) U/L accordingly. The levels of serum ALT, AST in IRI 6 h group were the highest (F=36.015, 18.241; P<0.05). The damage of liver tissues in IRI 6 h group was the most serious. The DNA fragmentation rates of liver tissues were (7.5±1.5)%, (9.2±2.2)%, (9.3±2.3)%, (12.6±2.4)%, (6.3±1.0)%, (5.4±0.9)%, (4.5±0.8)%, (4.5±1.1)% accordingly, which was the highest in IRI 6 h group (F=15.992, P<0.05). The levels of Ki-67 expression of liver tissues were (3.5±1.4), (5.6±1.8), (8.7±2.3), (13.7±2.4), (15.2±1.2), (20.5±2.2), (31.8±2.5), (2.4±1.2) / high power field accordingly, which was the highest in IRI 48 h group (F=261.707, P<0.05).

The liver IRI model can be successfully established by occluding the proper hepatic artery, and the optimum reperfusion duration of IRI is 6 h.