摘要目的 以健康青年小鼠为对照,分析应用超声造影(CEU)评估健康老年小鼠的肾脏血流灌注的特点. 方法 数字抽签随机选取健康C57BL/6J青年小鼠(1～2月龄)和老年鼠(18～20月龄)各12只,采用常规超声评估青年鼠和老年鼠的肾脏形态学、血流动力学,应用CEU评估两组的肾脏微血管灌注,测定造影剂灌注时间-强度曲线(TIC)相关参数[上升支斜率(A)、曲线下面积(AUC)、峰值强度(PI)、达峰时间(TTP)],实时定量评估分肾皮质的血流灌注. 结果 常规超声显示青年鼠和老年鼠两组间肾门、肾段和叶间肾动脉血流频谱差异无统计学意义(均P＞0.05).CEU显示老年鼠的TIC上升、较缓慢,与青年鼠比较,A减小(0.74±0.06比0.89±0.12,P＜0.05)、AUC增大(1420.08±208.30)db/s比(1261.41±34.65)db/s(P＜0.05)、TTP延长(7.75±0.88)s比(6.93±0.44)s(P＜0.05),PI差异无统计学意义(P＞0.05). 结论 CEU定量分析能够反映青年鼠与老年鼠肾脏血流灌注的差异,为进一步研究奠定基础.

abstractsObjective To explore the characteristics of renal cortical perfusion with contrastenhanced ultrasound (CEU)in elderly mice.Methods Randomly selected 12 healthy C57BL/6J young mice(aged 1-2 months)and 12 healthy elderly mice(aged 18-20 months)were assigned respectively into the control group and the experimental group.All mice were examined by color Doppler ultrasound and CEU.Renal morphology and hemodynamics were assessed with conventional ultrasound and CEU was used to assess renal microvascular perfusion,analyzing the time-intensity curve(TIC) and related parameters,including slope rate of ascending curve (A),area under curve (AUC),peak intensity (PI),and time to peak (TTP).Results Conventional ultrasound showed similar blood flow dynamics in the renal hilum artery,the renal segmental artery and the renal interlobar artery between the young and elderly mice groups(all P ＞0.05).Moreover,CEU showed slower ascendance of TIC in the elderly mice group(P ＜ 0.05).Furthermore,the elderly mice were associated with significantly decreased A (0.74 ± 0.06 vs.0.89 ± 0.12,P ＜ 0.05) and increased AUC (1420.08± 208.30)dB · s vs.(1261.41± 34.65)dB/s(P＜0.05),delayed TTP(7.75 ±0.88)s vs.(6.93± 0.44) s (P ＜ 0.05),and similar PI (P ＞ 0.05),compared with those in the young mice group.Conclusions Qualitative analysis of CEU is capable of detecting renal perfusion differences between young and elderly nice,which might lay a basis for further study.