超声造影评价大鼠肾脏冷缺血-再灌注损伤血流灌注

摘要

目的 应用超声造影评价大鼠肾脏冷缺血-再灌注损伤皮质血流灌注参数的变化及其与病理损伤的相关性,探讨静脉连续输注法超声造影评价肾血流灌注的价值.方法 雄性SD大鼠随机分为2组,假手术组(15只)仅切除右肾,冷缺血-再灌注损伤组(15只)建立肾脏冷缺血-再灌注损伤模型,分别于术后第1、3、7天取5只大鼠行肾脏超声造影,定量测定肾皮质峰值声学强度(A)、造影剂灌注速率(β)、血流量(A×β).统计分析肾皮质血流参数的变化及其与病理损伤的相关性.结果 假手术组与冷缺血-再灌注损伤组大鼠同组之间不同时间点、两组之间对应时间点之间比较血流参数A值均无显著差异(P＞0.05);冷缺血-再灌注损伤组术后第1天β值、A×β值降低,与假手术组比较差异有统计学意义(P＜0.05,P＜0.01).冷缺血-再灌注损伤组术后第3天β值、A×β值开始改善,但仍显著低于假手术组(P＜0.01);术后第7天β值、A×β值明显改善,与假手术组比较无显著差异(P＞0.05).经统计相关分析,肾小管坏死积分与A值无显著相关性(r=-0.43,P＞0.05);与β值、A×β值均成显著负相关(r=-0.75、-0.77,P＜0.01).结论 大鼠肾脏冷缺血-再灌注损伤皮质血流减少主要是由于血流灌注速度的降低所致;静脉连续输注法超声造影可定量监测肾皮质血流的变化.%Objective The aim of this study was to investigate the abnormal renal cortical haemodynamics and its correlation with nephropathy in rat models with cold ischemia-reperfusion injuries( CIRI ), and to evaluate the value of continuous infusion contrast-enhanced ultrasound ( CEUS ) in monitoring the anomalies of renal haemodynamics. Methods Thirty-four male Sprague-Dawley rats were randomly divided into two groups. Fifteen rats in sham-surgery group ( SSG ) were removed with their right kidneys only, and the other fifteen rats in the renal CIRI group were made as CIRI models. Five rats per subgroup were performed by CEUS ( continuous infusion of SonoVue ) after surgeries at day 1, 3 and 7, respectively. The values of the peak signal intensity ( A), the signal velocity ( β ), and the product of A and β ( A × β )representing as the regional renal blood flow of the region of interest ( ROI ) , were obtained. Correlations between renal hemodynamics parameters and renal tubular necrosis score ( TNS ) of CIRI rats were statistically analyzed. Results The value of parameters A had no significant difference at different time points within the same group or comparison between both SSG and CIRI groups at the same time points after surgeries ( P ＞0. 05 ). Compared with those in the SSG group after the surgeries, the values of β and A ×β in the CIRI group were significant lower at day 1 ( P ＜ 0. 05 , P ＜0. 01 ), which were still significant lower at day 3 ( P ＜0. 01 )and returned to normal at day 7 ( P ＞0. 05 ) . The value of tubular necrosis score had no significant correlation with the parameters of A ( γ = -0.43 ,P＞0. 05 ), but negative correlation with the values of parameters β and A × β ( γ = -0. 75, -0.77,P＜0. 01 ). ConclusionThe reduction of renal cortical blood flow is due to a decrease of β after renal CIRI.Continuous infusion CEUS can quantitatively assess several parameters of renal cortical haemodynamics.