Cell cycle redistribution of cultured cells after treatment with chemical radiation protectors.
The effect of two radioprotective agents (WR-1065 and WR-151326) was tested for their ability to modify cell cycle progression. Each protector was administered at a concentration of 4 mmol to exponentially growing cultures of V79 cells for periods of time up to 3 h. Under these conditions no cell toxicity was observed. At selected times up to and after removal of the protector, aliquots of cells were removed, counted and fixed in cold 70% ethanol. The cells were stained with DAPI in a 0.1% citrate solution and DNA histograms were obtained using a PARTEC PAS-II flow cytometer. The coefficient of variation of the G1 peaks obtained for unperturbed cell samples routinely ranged from 1.5 to 2.5%. During exposure, both radioprotectors effectively perturbed cell cycle progression, as characterized by a build-up of cells in S and G2 phases. After the protectors were removed, cells began to redistribute throughout the cell cycle. Twelve hours were required before cells exposed to WR-1065 approached levels commensurable with controls. In contrast, cells treated with WR-151236 required about 24 h to redistribute to control levels. These data demonstrate that different thiol-containing radioprotective compounds can differentially affect the progression and redistribution of exposed cells.
Sigdestad
C P
CP
Radiation Oncology Department, J.G. Brown Cancer Center, University of Louisville School of Medicine, KY 40292.
Guilford
W
W
Perrin
J
J
Grdina
D J
DJ
D000818:Animals; D002453:Cell Cycle / Q000187:drug effects*; D002460:Cell Line; D006224:Cricetinae; D004247:DNA / Q000032:analysis; D005434:Flow Cytometry; D066298:In Vitro Techniques; D008624:Mercaptoethylamines / Q000494:pharmacology*; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D013438:Sulfhydryl Compounds / Q000494:pharmacology*
D008624:Mercaptoethylamines; D011837:Radiation-Protective Agents; D013438:Sulfhydryl Compounds; C020174:N-(2-mercaptoethyl)-1,3-diaminopropane; C058704:3-(3-methylaminopropylamino)propylmercaptan; D004247:DNA