Abstract
Distinct fractional zones of cell membranes in sucrose gradients were obtainable from homogenates of rat liver up to 6 hr (females) and 12 hr (males) following an i.p. injection of CCl4 (0.2 ml/kg body wt.). CCl4 administration to rats caused a marked elevation of NADH-cytochrome c reductase activity in the liver cell membrane. There was a remarkable difference between sexes with respect to time-course of the changes of the enzyme activity, viz., a. peak was reached 6 hr after administration in female rats and 12 hr in male rats with normal activity at 6 hr. Neither mitochondrial fractions nor microsomal fractions of rat liver displayed any significant alterations in NADH-cytochrome c reductase activity 6 hr after CCl4 administration.
