c-ras-P21andGamma-glutamyltransferase(G-GT)activityanditsisoenzymesinratliverextractsweremeasuredafterpartialhepatectomy.TherewereG-GTactivitypeaksat12thand36thhourafteroperation,whilenodistinctisoenzymepatternswerefound.P21proteinexpressionoccurredbetween48and96hoursafterpartialhepatectomy.TheseresultssuggestthatthetemporaryincreaseofG-GTandP21proteinlevelisinvolvedintheprereplica-tivestageofliverregeneration.