诊断超声联合微泡对大鼠移植瘤血管通透性影响的实验研究

摘要

Objective To investigate the effects of transplantated tumor capillary permeability under microbubble enhanced diagnostic ultrasound exposure.Methods Fourty eight rats were randomly divided into four groups after Walker 256 carcinomas were subcutaneousely implanted,named the control group (A),microbubbles group (B),ultrasound group (C),microbubbles and ultrasound group (D).Using Evans blue(EB) as the indicator for tumor capillary permeability,the microbubbles were injected through the vein with diagnostic ultrasound frequency as 1.75 MHz,mechanical index as 1.4.The spillover of EB was estimated under confocal laser microscope,meanwhile the contents of EB in the tumor tissues were calculated according to the standard curve and spectrophotometry.Results EB spillover was observed around the capillaries in the group D,while EB spillover was only observable on capillary in group A,B and C.The EB content was also significantly higher than those in group A,B and C.Conclusions Exposure to both diagnostic ultrasound and microbubbles results in increased capillary permeability of rat tumor tissues,which might become a potential therapeutic method on clinical chemotherapy.%目的 研究诊断超声联合微泡对大鼠移植瘤血管通透性的影响.方法 将48只已建立Walker-256皮下移植瘤模型的SD大鼠随机分为4组:空白对照(A)组、单纯微泡剂(B)组、单纯超声(C)组和超声联合微泡(D)组.以伊文思蓝(Evens blue,EB)为指示剂,选择频率为1.75 MHz、机械指数为1.4的诊断超声持续照射肿瘤区5 min,经大鼠尾静脉注射/不注射微泡造影剂.使用分光光度计和标准曲线法测量大鼠肿瘤组织内EB含量变化,激光共聚焦显微镜观察EB外溢情况.结果 超声联合微泡可增加肿瘤组织微血管通透性.D组瘤内EB含量较A、B、C组明显增加(P＜0.05),血管周围EB外溢明显.A、B、C组EB含量比较差异无统计学意义(P＞0.05),血管周围均未见明显EB渗出.结论 在一定条件下,诊断超声联合微泡可明显提高辐照肿瘤组织血管通透性,这对临床肿瘤化疗患者具有潜在的应用意义.