探索红景天苷对大鼠肝脏缺血再灌注(IR)损伤的保护作用及其相关机制。

将54只SD大鼠随机分成3组(假手术组、IR组、红景天苷组)，每组各18只。实验前7 d，红景天苷组每天腹腔注射方式给药(30 mg·kg^－1·d^－1)，IR组和假手术组以相同体积等渗NaCl溶液代替。建立大鼠肝脏70%IR模型，缺血45 min后恢复血供，再灌注后4、8、16 h每组各处死6只大鼠，立即下腔静脉采血并取肝组织标本。检测大鼠再灌注后不同时间点血清ALT、AST水平；蛋白质印迹法检测凋亡相关蛋白B细胞淋巴瘤/白血病-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、半胱氨酰天冬氨酸特异性蛋白酶(Caspase)-3、Caspase-8、Caspase-9的表达；免疫组织化学法观察上述相关凋亡相关分子阳性细胞表达并进行半定量分析；流式细胞仪检测肝细胞凋亡率。采用单因素方差分析比较各组大鼠再灌注后不同时间点血清ALT和AST含量、凋亡相关蛋白相对表达量及细胞凋亡率。

与假手术组相比，IR组各时间点ALT、AST均上升，红景天苷组ALT、AST均低于IR组(P均<0.05)。与IR组相比，红景天苷组Bax、Caspase-3、Caspase-8、Caspase-9表达降低，Bcl-2表达增加；2组再灌注后各时间点Bcl-2、Bax相对表达量差异均具有统计学意义，再灌注后4 h Caspase-3相对表达量差异有统计学意义，再灌注后8、16 h Caspase-8、Caspase-9相对表达量差异有统计学意义(P均<0.05)。再灌注后8 h，红景天苷组、IR组和假手术组肝细胞凋亡率分别为(24.09±2.43)%、(45.71±3.19)%和(5.46±0.34)%，差异有统计学意义(F＝4.08，P<0.05)。

红景天苷预处理可以减轻肝脏缺血再灌注损伤，可能与其抑制细胞凋亡内源性和外源性途径有关。

To explore the protective effect of salidroside on hepatic ischemia reperfusion (IR) injury and its correlative mechanisms.

Fifty-four healthy SD rats were randomly divided into 3 groups (sham group, IR group, salidroside treatment group) with 18 rats in each group. The administration dosage of salidroside was 30 mg·kg^-1·d^-1 which was administrated 7 days before modeling by intraperitoneal injection, and rats in other two groups were treated with the same volume of isotonic sodium chloride solution. The blood supply of left and middle lobe of liver was obstructed (70% IR model) for 45 minutes, and all the rats were killed at the time points of 4, 8 and 16 hours after reperfusion, respectively. Blood and liver tissue samples were collected soon after death. The concentration of serum ALT and AST was detected; expression of B-cell leukemia/lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), cysteine-dependent aspartate-directed protease (Caspase)-3, -8, -9 were detected by Western blot; immunohistochemistry was used to detected the above apoptotic related proteins positive hepatocytes and were semi-quantity analyzed; Flow cytometry was used to detect the apoptosis rate of hepatocytes. One-way analysis of variance was used to compare the concentration of serum ALT and AST, expression of apoptotic related proteins and hepatocytes apoptosis rate.

The serum level of ALT and AST in the IR group were higher than sham group and salidroside treatment group (P all<0.05). The expression of Bax, Caspase-3, -8, -9 in salidroside treatment group was lower than IR group, while the expression of Bcl-2 was higher than IR group. There was statistic difference for the relative expression of Bax and Bcl-2 at different time points, Caspase-3 at 4 hours after reperfusion and Caspase-8, -9 at 8, 16 hours after reperfusion between salidroside treatment group and IR group (P all<0.05). The apoptosis rates of salidroside treatment group, IR group and sham group at 8 hours after reperfusion were (24.09±2.43)%, (45.71±3.19)% and (5.46±0.34)%, which had statistic difference (F=4.08, P<0.05).

Salidroside pretreatment can relieve hepatic ischemia reperfusion injury, which may be related to inhibition of cell apoptosis through the endogenous and exogenous pathway.