Differential repair of potentially lethal damage in exponentially growing and quiescent 9L cells

Journal Article · Sun Apr 01 04:00:00 EDT 1990 · Radiation Research; (USA)

DOI:https://doi.org/10.2307/3577580· OSTI ID:6973911

Mendonca, M S; Rodriguez, A; Alpen, E L ^[1]

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1. Lawrence Berkeley Laboratory, Berkeley (USA)

The alteration of potentially lethal damage repair by postirradiation treatment with hypertonic saline (0.5 M PBS) was investigated in exponentially growing and quiescent 9L cells in vitro. A single dose of X rays (8.5 Gy) immediately followed by a 30-min treatment with hypertonic PBS at 37 degrees C reduced the survival of exponentially growing 9L cells by a factor of 13-18 compared to survival of irradiated immediately and delayed-plated cells, while the survival of quiescent cells was reduced by only a factor of 5-8. Survival curves confirmed the relative resistance of the quiescent 9L cells versus exponentially growing 9L cells to X rays plus hypertonic treatment. Both the slope and the shoulder of the survival curve were reduced to a greater extent in exponentially growing cells than in the quiescent cells by hypertonic treatment. The response of quiescent cells cannot be explained by either the duration of hypertonic treatment or the redistribution of the cells into G1 phase. We show that quiescent 9L cells can recover from hypertonically induced potentially lethal damage when incubated under conditions which have been found to delay progression through the cell cycle, and postulate that an altered chromatin structure or an enhanced repair capacity of quiescent 9L cells may be responsible for their resistance.

• OSTI ID: 6973911
• Journal Information: Radiation Research; (USA), Journal Name: Radiation Research; (USA) Vol. 122:1; ISSN RAREA; ISSN 0033-7587
• Country of Publication: United States
• Language: English

Related Subjects

560120* -- Radiation Effects on Biochemicals
Cells
& Tissue Culture
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALI METAL COMPOUNDS
ANIMAL CELLS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CELL CYCLE
CELL DIVISION
CHLORIDES
CHLORINE COMPOUNDS
DNA REPAIR
ELECTROMAGNETIC RADIATION
HALIDES
HALOGEN COMPOUNDS
IONIZING RADIATIONS
RADIATIONS
RADIOSENSITIVITY
RADIOSENSITIVITY EFFECTS
RECOVERY
REPAIR
SODIUM CHLORIDES
SODIUM COMPOUNDS
SURVIVAL CURVES
TUMOR CELLS
X RADIATION