特利加压素通过抑制HIF-1α表达水平和细胞凋亡减轻脓毒性休克大鼠急性肾损伤

Terlipressin alleviates acute kidney injury in septic shock rats by inhibiting HIF-1α and apoptosis

目的探讨特利加压素在保护大鼠脓毒性休克急性肾损伤(AKI)中的作用。方法32只雄性SD大鼠随机分为对照组、脓毒性休克组、去甲肾上腺素组和特利加压素组,每组8只。脓毒性休克组采用静脉注射脂多糖(LPS,10 mg/kg)建立大鼠脓毒性休克AKI模型,去甲肾上腺素组和特利加压素组分别在LPS处理后滴定式给予去甲肾上腺素或特利加压素,维持大鼠平均动脉压(MAP)在基线值的80%~90%。检测指标为血清肌酐(Cr)、尿素氮(BUN)、肾脏病理损伤评分、肾脏组织中肾损伤标志物中性粒细胞明胶酶相关脂质运载蛋白(NGAL)、肾脏细胞凋亡及凋亡相关蛋白B细胞淋巴瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)及活化的含半胱氨酸的天冬氨酸蛋白水解酶3(cleaved caspase 3)、缺氧诱导因子-1α(HIF-1α)的表达。结果静脉注射LPS后30 min内大鼠出现明显血压下降,心率增快,与基线值及对照组比较差异有统计学意义(P<0.05);去甲肾上腺素和特利加压素均能有效维持脓毒性休克大鼠的血压,并降低心率(P<0.05)。脓毒性休克组的血清Cr、肾损伤标志物NGAL mRNA水平,以及肾脏病理损伤评分、Bax/Bcl-2及cleaved caspase 3表达水平、HIF-1α蛋白表达水平显著高于对照组,差异均有统计学意义(P<0.05);与脓毒性休克组比较,特利加压素组血清Cr、NGAL mRNA水平,以及肾脏病理损伤评分及cleaved caspase 3表达水平、HIF-1α蛋白表达水平显著降低,差异均有统计学意义(P<0.05)。在原位末端标记法(TUNEL)分析中,脓毒性休克组肾组织细胞凋亡率显著高于对照组,差异有统计学意义(P<0.05),且多集中于肾小管区域;特利加压素组和去甲肾上腺素组的细胞凋亡率明显低于脓毒性休克组,差异有统计学意义(P<0.05),且特利加压素组较去甲肾上腺素组更低。结论特利加压素可能通过减少HIF-1α表达水平及细胞凋亡改善大鼠脓毒性休克AKI。

Objective To explore the role of terlipressin in protecting acute kidney injury(AKI)in septic shock rats.Methods Thirty-two male SD rats were randomly divided into 4 groups,namely the control group(n=8),the septic shock group(n=8),the norepinephrine group(n=8)and the terlipressin group(n=8).In the septic shock group,intravenous lipopolysaccharide(LPS,10 mg/kg)was used to establish a model of AKI in septic shock rats.The norepinephrine group and terlipressin group were titrated with norepinephrine or terlipressin after LPS treatment to maintain the mean arterial pressure(MAP)at 80%-90%of the baseline.The serum creatinine(Cr),urea nitrogen(BUN),kidney pathology score,neutrophil gelatinase-associated lipocalin(NGAL,a kidney injury biomarker),kidney cell apoptosis,and expression of apoptosis-related molecules B-cell lymphoma-2(Bcl-2),Bcl-2 associated X protein(Bax),cleaved caspase 3 and hypoxiainducible factor-1α(HIF-1α)were detected.Results Within 30 minutes after intravenous injection of LPS,the blood pressure of the rats decreased and the heart rate increased significantly,and the differences were statistically significant compared with the baseline value and the control group(both P<0.05).Norepinephrine and terlipressin could effectively maintain blood pressure in septic shock rats,and decreased heart rate(both P<0.05).Serum Cr,m RNA level of kidney injury marker NGAL,kidney injury pathological scores,and the protein expression of Bax/Bcl2,cleaved caspase 3,and HIF-1αin the septic shock group were significantly higher than those in the control group,and the differences were statistically significant(all P<0.05).Compared with the septic shock group,the serum Cr and NGAL m RNA level,as well as the kidney injury pathological scores,the protein expression of cleaved caspase 3 and HIF-1αin the terlipressin group were significantly decreased,and the differences were statistically significant(all P<0.05).In the terminal deoxynucleotidyl transferase d UTP nick end labeling(TUNEL)analysis,the apoptosis rate of renal tissue in the septic shock group was significantly higher than that in the control group,and the difference was statistically significant(P<0.05),and it was mostly concentrated in the renal tubular area.The apoptosis rates in the terlipressin and norepinephrine groups were significantly lower than those in the septic shock group,and the differences were statistically significant(both P<0.05).And the apoptosis rate in the terlipressin group was lower than that in the norepinephrine group.Conclusion Terlipressin might improve AKI in septic shock rats by reducing HIF-1αand cell apoptosis.