An Acidic Extracellular Environment Reduces the Fixation of Radiation Damage

Publisher Website
Google Scholar
Abstract
Chinese hamster ovary cells in exponential growth were irradiated with .gamma.- or X-rays in an acidic or alkaline extracellular environment. Incubation in acid medium during or after irradiation reduced the degree of fixation of potentially lethal lesions. Fixation and repair of acid-modified damage occurred with a half-time of 9 to 10 min. The rate of repair of sublethal damage was unaffected by hydrogen ion concentration and progressed with a half-time of 30 min. An acid environment modified only survival of exponentially growing cells; unfed plateau-phase cultures were unaffected.