title: Membrane damage effect of therapeutic ultrasound on Ehrlich ascitic tumor cells.
abstract: OBJECTIVE
  The biologic effects and the underlying mechanisms of Ehrlich ascitic tumor (EAT) cells induced by ultrasound were investigated in this study.
  
  
  METHODS
  Cells were subjected to ultrasonic irradiation with a frequency of 2.17 MHz and an intensity of 3 W/cm(2) for variable periods of time. Trypan blue exclusion was used to detect the integrity of cellular membrane; the membrane permeability was investigated by the incorporation of fluorescein isothiocyanate dextran during ultrasound exposure; and the cell membrane ultrastructure changes were observed under a scanning electron microscope. The potential mechanism was estimated from the generation of hydroxyl radicals, the lipid peroxidation levels, and intracellular reactive oxygen radicals production.
  
  
  RESULTS
  The cell membrane damage effects induced by ultrasound increased with a prolonged exposure time; the fluorescent rates of the cells irradiated with ultrasound for 30 and 60 seconds were 11.46% and 18.50%, respectively; the amount of hydroxyl radicals in 30 (26.10 U/mL) and 60 seconds (28.47 U/mL) were significantly enhanced, compared with the control group (24.44 U/mL); then, the level of lipid peroxidation was also changed from 0.27 to 0.54 (30 seconds) and 1.21 nmol/mL (60 seconds).
  
  
  CONCLUSIONS
  Shear forces and free radicals produced by acoustic cavitation may play important roles in these actions.
authors.affiliation: College of Life Sciences and Natural Pharmaceutical Chemistry, Shaanxi Normal University, Xi'an China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Hao
authors.forename: Quanhong
authors.initials: Q
authors.lastname: Liu
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Wang
authors.forename: Pan
authors.initials: P
authors.lastname: Wang
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.forename: Wan Yan
authors.initials: WY
authors.lastname: Tong
mesh_terms: D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000000981:diagnostic imaging* / Q000628:therapy*; D002462:Cell Membrane / Q000000981:diagnostic imaging*; D002463:Cell Membrane Permeability; D002470:Cell Survival; D016650:Fluorescein-5-isothiocyanate / Q000494:pharmacology; D017665:Hydroxyl Radical; D015227:Lipid Peroxidation; D051379:Mice; D008855:Microscopy, Electron, Scanning; D017382:Reactive Oxygen Species; D013010:Sonication; D016896:Treatment Outcome; D014343:Trypan Blue / Q000494:pharmacology; D014464:Ultrasonic Therapy / Q000379:methods*; D014463:Ultrasonography
chemical_list: D017382:Reactive Oxygen Species; D017665:Hydroxyl Radical; D016650:Fluorescein-5-isothiocyanate; D014343:Trypan Blue