Effect of X/XO on autonomous PKC activity isolated from slices with DEAE column chromatography. Slices were incubated with X/boiled XO (open squares, n = 5), X/XO (open circles, n = 5), X/XO + SOD (filled squares, n = 5), or X/XO + catalase (filled circles,n = 5) for 10 min, and the incubations were followed by perfusion with normal saline solution for 45 min. Then the slices were frozen on dry ice and homogenized; the soluble fraction of the homogenates was applied to a DEAE column. PKC was eluted from the column with either 0.1 or 0.25 m NaCl (arrows), and autonomous PKC activity was measured in each fraction as described in Materials and Methods.