Abstract
By a simple modification of the assay of glutathione by yeast apoglyoxalase, both total and reduced glutathione have been determined. Reduction of oxidized glutathione is brought about by the enzyme preparation without additional manipulation. In the cerebral tissues of rats and guinea pigs rapidly fixed in situ, total glutathione approximated to 3 equivalents of reduced glutathione/g and the oxidized form, to 0.05-0.1 /xeq/g. In cerebral tissues removed rapidly at room temperature, from several mammalian species, the content of total glutathione differed little from that quoted, but oxidized glutathione had risen to 0.3-1.5 /xeq/g. During respiration of cerebral tissues in vitro their total glutathione could be maintained at concentrations found in vivo by incubation in oxygenated glucose media containing added glutathione. If glutathione was not added, lower values were found in the tissue. Oxidized glutathione during experiments in vitro was slowly reduced, but after 2 hr. at 37[degree] remained much higher than in the tissue in vivo.