【摘要】 目的观察不同强度的体外低频低强度超声对颈动脉粥样硬化斑块中平滑肌细胞增殖和凋亡的影响。方法将新西兰大白兔按照高脂饮食加空气干燥法建立颈动脉粥样硬化模型,随后随机分成正常对照组(对照组,6只)和4个超声组(每组6只),4个超声组根据超声的强度和时间分别为A组(0．5 W/cm~2,5 min/d)、B组(0．5 W/cm~2,10 min/d)、C组(1 W/cm~2,5 min/d)和D组(1 W/cm~2,10 min/d),超声作用每日1次,20 d之后取颈动脉手术部位做病理切片。分别用增殖细胞核抗原(PCNA)染色和末端脱氧核酸转移酶介导的脱氧三磷酸尿苷(dUTP)-生物素平移末端标记法(TUNEL)染色分析血管平滑肌细胞(VSMC)增殖和凋亡情况,并计算细胞增殖率(PCNA%)和细胞凋亡率(TUNEL%)。结果各超声组颈动脉内膜内PCNA阳性细胞率较对照组有不同程度的减少,其中B、C、D组与对照组比较差异有统计学意义(P＜0．05)；各超声组颈动脉内膜中TUNEL阳性细胞率较对照组有不同程度增加,其中B、C、D组与对照组比较差异有统计学意义(P＜0．05)。B、C、D组相互比较PCNA%和TUNEL%,差异均无统计学意义(P＞0．05)。结论体外低频低强度(0．5 W/cm~2,10 min/d)超声具有明显诱导家兔颈动脉粥样硬化血管平滑肌细胞凋亡和抑制增殖的作用。更多还原

【Abstract】 Objective To investigate the effects of low frequency ultrasound (LFU) on the proliferation and apoptosis of smooth muscle cells (SMCs) in rabbits with carotid atherosclerosis(CA).Methods CA models were established in 30 New Zealand rabbits using a high fat diet and air-drying.They were randomly divided into a control group and four LFU groups:group A received 0.5 W/cm~2 LFU for 5 min/d,group B 0.5 W/cm~2 for 10 min/d, group C 1 W/cm~2,5 min/d,and group D 1 W/cm~2,10 min/d.The rabbits’ carotid arteries were autopsied after 20 d of the LFU treatment.The expression of PCNA and TUNEL staining were used to explore the proliferation and apopto- sis of SMCs,and the proliferation rates (PRs) and apoptosis rates (ARs) were calculated.Results Compared with the control group,the PRs in groups B,C and D were significantly lower,while the ARs in groups B,C and D were significantly higher.There was no significant difference in ARs or PRs among groups B,C and D.Con- clusion LFU can induce SMC apoptosis and inhibit SMC proliferation in rabbits with CA.更多还原