急性缺血性卒中小鼠注射钆对比剂后肾脏钆沉积及肾损伤的实验研究

Experimental study on renal gadolinium deposition and renal injury in mice with acute ischemic stroke after injection of gadolinium contrast agent

目的研究急性缺血性卒中(AIS)小鼠静脉注射钆喷酸葡胺(Gd-DTPA)后AIS和Gd-DTPA的协同效应对肾组织钆沉积和毒性损伤的影响。方法将40只健康的C57BL/6雄性小鼠采用随机数字表法均分为AIS组和假手术组,随后每组又均分为Gd-DTPA注射亚组和生理盐水注射亚组。每组均于术后4.5 h和1 d注射。最终将小鼠分为4组:A组(AIS组+Gd-DTPA)、B组(假手术组+Gd-DTPA)、C组(AIS组+生理盐水)、D组(假手术组+生理盐水),每组10只。每组在末次注射后第1天和第28天各随机选取5只小鼠进行实验分析。采用电感耦合等离子体质谱(ICP-MS)分析钆沉积浓度;采用血清生化和病理染色分析血清肌酐(Scr)和尿酸(UA)水平、肾小管损伤评分以及系膜基质指数。2组间比较采用独立样本t检验或配对t检验;多组间比较采用双因素方差分析,组间进一步两两比较采用Tukey检验。结果末次注射后第1天和第28天,A组小鼠肾组织钆浓度均高于B组(均P<0.05),Scr和UA值、肾小管损伤评分均高于其他各组(均P<0.05);A组末次注射后第28天的系膜基质指数也高于其他各组(P<0.05)。HE染色显示A组的损伤程度最重、范围最广。此外,A组末次注射后第28天时的肾小管损伤评分较第1天降低(P<0.05)。结论AIS和Gd-DTPA的协同效应可能会增加肾组织钆沉积量以及加重肾毒性损伤。

Objective To investigate the synergistic effect of acute ischemic stroke(AIS)and Gd-DTPA on the gadolinium deposition and nephrotoxicity after intravenous injection of Gd-DTPA in a mouse model of acute ischemic stroke(AIS).Methods Forty healthy male C57BL/6 mice were randomly divided into AIS group and sham group by random number table method,and then each group was further divided into Gd-DTPA and saline injection subgroups.Each group was injected at 4.5 hours and 1 day after modeling.Finally,this experiment was divided into 4 groups(n=10):group A(AIS group+Gd-DTPA),group B(Sham group+Gd-DTPA),group C(AIS group+saline),group D(Sham group+saline).Five mice were randomly selected from each group on day 1 and day 28 after last injection for experimental analysis.The concentration of gadolinium deposition was analyzed with inductively coupled plasma mass spectrometry(ICP-MS);and the levels of serum creatinine(Scr)and uric acid(UA),tubular injury score and mesangial matrix index were analyzed with serum biochemistry and pathological staining.Independent sample t test or paired t test was performed between 2 groups,and two-way analysis of variance(two-way ANOVA)was performed among 4 groups,following by post-hoc multiple comparisons with Tukey test.Results On day 1 and day 28 after the last injection,the group A showed higher Gd concentration than the group B(all P<0.05),higher Scr and UA levels and tubular injury scores than the other groups(all P<0.05).The mesangial matrix index was increased in the group A compared to the other groups on day 28 after the last injection(P<0.05).Most severe and extensive damage was observed in the group A on HE staining.In addition,the tubular injury score in the group A on day 28 after the last injection was lower than on day 1(P<0.05).Conclusion The synergistic effect of AIS and Gd-DTPA may increase the Gd concentration and aggravate the nephrotoxicity.