Problems in determination of glutathione in rat liver supernatant
Di Simplicio, P.; Palmi, M.; Segre, G.
Bollettino della Societa Italiana di Biologia Sperimentale 54(22): 2234-2240
1978
ISSN/ISBN: 0037-8771 PMID: 38818 Document Number: 129795
The supernatant obtained by ultracentrifugation of buffered rat liver homogenates, when treated by the acid precipitation method, yields a mixture of reduced and oxidized (GSH and GSSG) glutathione, which can be assayed by an enzymatic procedure. When, instead of the standard acid process, a neutral precipitation is used, total glutathione values considerably rise over a 6 h period. This behavior is due to a thioltransferase which, by rupturing GSH bonds from protein sulfhydryl groups, forms additional GSSG. The treatment described in the literature permits determination of soluble glutathione but not that portion which is linked to proteins. Neutral precipitation shows that GSH can exist, linked to proteins. This leads to an important conclusion regarding the known increase in total glutathione observed after CCl4 poisoning. This increase is probably due to denaturation of liver proteins containing GSH linked to protein.