title: Effects of nimodipine and dexamethasone on low-level CO2 laser-induced release of 51chromium from canine 2C5 gliosarcoma cells.
abstract: Low-energy penumbral irradiation of surgical lasers may produce undesirable effects on surrounding tissues. This study used a 51Cr cell labeling technique to determine if gliosarcoma cells could be therapeutically protected prior to their exposure to low-power laser irradiation. Canine 2C5 gliosarcoma cells with intracellular 51Cr were treated with nimodipine and/or dexamethasone and then exposed to low-power levels of CO2 laser. The 51Cr was released from the cells in a dose-dependent fashion following exposure to laser energy. Correlative analysis of the data indicated that a strong direct relationship between laser fluence and 51Cr release did exist for controls and drug-treated groups with coefficients of correlation r > or = +0.90 and coefficients of determination r2 > or = 0.82. However, comparison of the data from the drug-treated and control groups found that there was no significant difference between them (P > .05). Therefore, no protective or detrimental effects were observed with the use of nimodipine and/or dexamethasone on the gliosarcoma cells as tested in this system. Further investigation is necessary in order to define the mechanisms by which low-power level lasers affect these cells. These effects do not appear to be mediated through localization of mechanisms to the cell membranes or their constituent Ca2+ channels.
authors.affiliation: Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, Tennessee 37232.
authors.forename: D W
authors.initials: DW
authors.lastname: Van Kooten
authors.forename: R J
authors.initials: RJ
authors.lastname: Maciunas
authors.forename: R S
authors.initials: RS
authors.lastname: Carver
mesh_terms: D000818:Animals; D015220:Calcium Channels / Q000187:drug effects / Q000528:radiation effects; D002245:Carbon Dioxide; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D002857:Chromium / Q000493:pharmacokinetics* / Q000528:radiation effects; D002860:Chromium Radioisotopes; D003907:Dexamethasone / Q000008:administration & dosage / Q000494:pharmacology*; D004285:Dogs; D004307:Dose-Response Relationship, Radiation; D004338:Drug Combinations; D018316:Gliosarcoma / Q000378:metabolism*; D007834:Lasers; D009553:Nimodipine / Q000008:administration & dosage / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
chemical_list: D015220:Calcium Channels; D002860:Chromium Radioisotopes; D004338:Drug Combinations; D002857:Chromium; D002245:Carbon Dioxide; D009553:Nimodipine; D003907:Dexamethasone