Ultrasound combined with microbubble enhanced eNOS expression and NO release in endothelial cells in vitro

Abstract

Objective To assess the enhancement effect of diagnostic ultrasound combined with microbubbles in the generation of endothelial nitric oxide synthase(eNOS)and nitric Oxide(NO)in endothelial cells.Methods Normal cultured human umbilical vein endothelial cells(HUVEC)were divided into blank control group(A group),simple microbubble group(B group),simple ultrasound group(C group)and ultrasound combined with microbubble group(D group).According to different conditions,group D was divided into three sub-groups:different time groups(1 min,5 min,10 min);different machinery index(MI)groups(0.09,0.4,1.0),different microbubble concentration groups(5×10~8/ml,2.5×10~8/ml,1.25×10~8/ml).Cell morpha was observed in the light microscope immediately and 24 h after the intervention,respectively.RT-PCR was used to measure the relative expression of eNOS in cells.NO kit was used to measure the NO Ievels in culture medium.And statistical methods were used to analyse the experimental data.Results NO and eNOS were significantly higher in group D than the other three groups.When MI=1.0,microbubble concentration=2.5×10~8/ml,and irradiation time=10 min,the increase of eNOS and NO in group D was the most obvious.Furthermore,the cell morphology had no significant change in the light microscope immediately and 24 h after the intervention.Conclusions Ultrasound combined with microbubble can increase the generation of eNOS and NO in endothelial cells. Key words: Ultrasound; Microbubble; Endothelial cells; Nitric oxide; Nitric oxide synthase