Miller D L, Thomas R M, Frazier M E
Biology and Chemistry Department, Battelle Pacific Northwest Laboratories, Richland, WA 99352.
Ultrasound Med Biol. 1991;17(7):729-35. doi: 10.1016/0301-5629(91)90106-7.
Direct exposure of cells to vigorous ultrasonic cavitation results predominantly in mechanical cell lysis, but latent effects due to production of toxic sonochemicals can also be present. Phosphate buffered saline (PBS) was exposed to 1.61 MHz ultrasonic cavitation at 20 degrees C in a rotating tube exposure system to build up sonochemical products. Single strand DNA breaks (SSBs) were then induced by treating Chinese hamster ovary (CHO) cells with the cavitated PBS for 30 min on ice. The SSBs resided in viable cells, as evidenced by their ability to repair the breaks when warmed. This indirect effect could be explained by the action of cavitation-generated hydrogen peroxide that had built up (e.g., to 16 microM after 30 min exposure) in the PBS. Dissolution of argon gas in the PBS before exposure enhanced the SSB effect and the H2O2 production. Addition of catalase to the cavitated PBS before cell treatment eliminated the H2O2 and the SSB gamma effect. Tests with hydrogen peroxide showed that 16 microM H2O2 treatment for 30 on ice was as effective as 1 Gy dose of 60Co gamma rays in producing single strand breaks. The SSB effect of H2O2 and gamma rays was reduced by addition of the radical scavenger cysteamine to the cells before treatment, but cysteamine did not reduce the SSB effect of direct exposure to ultrasonic cavitation. These results help to clarify the potential for genetic effects from ultrasonic cavitation. These effects help to clarify the potential for genetic effects from ultrasonic cavitation.
细胞直接暴露于强烈的超声空化作用下主要会导致机械性细胞裂解，但由于有毒声化学物质的产生也可能存在潜在影响。在旋转管暴露系统中，将磷酸盐缓冲盐水（PBS）于20℃暴露于1.61MHz的超声空化作用下以积累声化学产物。然后，通过在冰上用空化的PBS处理中国仓鼠卵巢（CHO）细胞30分钟来诱导单链DNA断裂（SSB）。这些SSB存在于活细胞中，这可通过它们在升温时修复断裂的能力得到证明。这种间接效应可以用在PBS中积累的空化产生的过氧化氢的作用来解释（例如，暴露30分钟后达到16微摩尔）。暴露前在PBS中溶解氩气增强了SSB效应和过氧化氢的产生。在细胞处理前向空化的PBS中添加过氧化氢酶消除了过氧化氢和SSBγ效应。用过氧化氢进行的测试表明，在冰上用16微摩尔过氧化氢处理30分钟在产生单链断裂方面与1戈瑞剂量的60Coγ射线一样有效。在处理前向细胞中添加自由基清除剂半胱胺可降低过氧化氢和γ射线的SSB效应，但半胱胺不会降低直接暴露于超声空化作用下的SSB效应。这些结果有助于阐明超声空化作用产生遗传效应的可能性。这些效应有助于阐明超声空化作用产生遗传效应的可能性。
