Bernard Shacter

Interrelations in Respiratory, Phosphorylative, and Mitotic Activity of Ehrlich Ascites-Tumor Cells: Influence of Sulfhydryl Reagents

Interrelationships between the respiratory, phosphorylative, and mitotic activity of Ehrlich ascites-tumor cells have been studied in vitro by exposing the cells to graded concentrations of agents affecting these activities and comparing the relative changes produced. Previous studies determining the influences of diriitrophenol and stilbestrol indicated that the rate of cell division, as measured by uptake of radioactive phosphorus into deoxyribonucleic acid (DNA), may be independently related to both the respiratory rate and the availability of high-energy phosphate (1,2). The studies were extended in the present investigation with determination of the effects of several sulfhydryl reagents. The importance of sulfhydryl-containing compounds in numerous biological processes, including cell respiration and division, has been demonstrated repeatedly (3,4-).4 Much of this information has been gained through detection of changes in the metabolic and functional activities of cells effected by reagents reacting readily with and destroying the sulfhydryl moiety of these compounds. Three such sulfhydryl reagents were employed in the present experiments: p-chloromercuribenzoic acid, a mercaptide-forming agent, o-iodosobenzoic acid, an oxidizing agent, and nitrogen mustard (HN2),s an alkylating agent.