蛋白酶激活受体-1拮抗剂对兔心脏骤停后综合征中肾损伤的保护作用及机制

The protective effects and mechanism of protease-activated receptor-1 antagonists on kidney injury in rabbits with post-cardiac arrest syndrome

目的:探讨蛋白酶激活受体-1(PAR-1)拮抗剂对心脏骤停后综合征(PCAS)中肾损伤的影响及机制。方法:将日本大耳白兔随机分为假手术组(n=5)、PCAS组(n=10)、PAR-1拮抗剂组(n=10)。采用窒息性心脏骤停法制备兔PCAS模型。PAR-1拮抗剂组于心肺复苏后10 min给予静脉滴注PAR-1拮抗剂SCH79797(25μg/kg),其余各组给予等量生理盐水静脉滴注。72 h后取股静脉血检测血清肌酐和胱抑素C水平;取肾组织制备石蜡切片后行HE染色;采用TUNEL法测定肾脏细胞凋亡情况;应用Western blot测定肾组织半胱天冬酶(casepase)-3、细胞外调节蛋白激酶(ERK)活化情况。结果:与假手术组相比,PCAS组血清肌酐和胱抑素C水平明显上升,肾组织有大量炎性细胞浸润,凋亡细胞数显著增多,有催化活性的caspase-3裂解片段(cleaved caspase-3)表达增高,磷酸化ERK(p-ERK)表达减少(P<0.05)。与PCAS组相比,PAR-1拮抗剂组肾组织损伤减轻,血清肌酐和胱抑素C水平明显下降,凋亡细胞数减少,cleaved caspase-3表达降低,而p-ERK表达显著增高(P<0.05)。结论:PAR-1拮抗剂SCH79797能抑制PCAS兔肾组织的炎症反应和细胞凋亡,可能与ERK信号通路激活有关。

Objective： To investigate the effects and mechanism of protease-activated receptor] （PAR-1） antagonists on kidney injury in rabbits with post-cardiac arrest syndrome（PCAS）. Methods： Japanese white rabbits were randomly divided into three groups： sham group （n = 5）, PCAS group（n = 10） and PAR-1 antagonist group （n = 10）. PCAS models were established by using asphyxia-induced cardiac arrest. Rabbits in PAR-1 antagonist group were given SCH79797 （25 μg/kg ） by intravenous infusion after 10 min of eardiopulmonary resuscitation. The other two groups were given equal amount of saline. Femoral vein blood was collected to examine serum levels of creatinine and cystatin C after 72 h. Then, rabbits were sacrificed, and histomorphology and apoptosis of kidney were analyzed by HE staining and TUNEL respectively. Western blot was performed to determine the activation of casepase 3 and extracellular regulated protein kinases （ERK）. Resuits zCompared with sham group, serum levels of creatinine and cystatin C were significantly elevated in PCAS group, and increased apoptosis, inflammatory cells infiltration, elevated expression of cleaved caspase-3, and down regulated ERK phosphorylation （p-ERK） were also observed in kidney of PCAS rabbits （P^0. 05）. Compared with PCAS group, the serum levels of cystatin C and creatinine were markedly reduced in PAR-1 antagonist group, the injury and apoptosis of kidney were attenuated and level of cleaved caspase-3 was decreased, but level of ERK phosphorylation was significantly increased in PAR-1 antagonist group （P〈0.05）. Conclusion：PAR-1 antagonist SCH79797 inhibits inflammation and apoptosis in kidney possibly by activating ERK pathway in rabbits with PCAS.