title: Generation of ROS in cells on exposure to CW and pulsed near-infrared laser tweezers.
abstract: We report the results of a study on generation of reactive oxygen species (ROS) and changes in the membrane potential of mitochondria of carcinoma of cervix (HeLa) and Chinese hamster ovary (CHO) cells following exposure to continuous wave (cw) or pulsed Nd: YAG laser (1064 nm). For a given laser irradiation, the generation of ROS and induced changes in the membrane potential of mitochondria were more pronounced for HeLa cells as compared to CHO cells. However, in both the cells the laser dose required to elicit a given change was much lower with pulsed laser exposure compared to that required with a cw laser exposure. This suggests involvement of photothermal effects in the laser irradiation induced changes. Mechanistic studies using quenchers for ROS suggest that laser irradiation leads to generation of hydroxyl radicals.
authors.affiliation: Biomedical Applications Section, R & D BLOCK D, Centre for Advanced Technology, Indore, 452 013, India. smohanty@cat.ernet.in
authors.forename: Samarendra Kumar
authors.initials: SK
authors.lastname: Mohanty
authors.forename: Mrinalini
authors.initials: M
authors.lastname: Sharma
authors.forename: Pradeep Kumar
authors.initials: PK
authors.lastname: Gupta
mesh_terms: D000818:Animals; D016466:CHO Cells; D002478:Cells, Cultured; D006224:Cricetinae; D006367:HeLa Cells; D006801:Humans; D007259:Infrared Rays; D007834:Lasers; D008564:Membrane Potentials / Q000528:radiation effects; D008846:Micromanipulation / Q000295:instrumentation* / Q000379:methods; D008928:Mitochondria / Q000502:physiology / Q000528:radiation effects; D051336:Mitochondrial Membranes / Q000378:metabolism / Q000528:radiation effects; D009354:Neodymium; D010777:Photochemistry; D017382:Reactive Oxygen Species / Q000378:metabolism* / Q000528:radiation effects*; D013696:Temperature; D013997:Time Factors
chemical_list: D017382:Reactive Oxygen Species; D009354:Neodymium