The gaseous metabolism of the isolated perfused normal and choline-deficient liver of the rat.

The gaseous metabolism of isolated perfused livers from normal and cholinedeficient rats has been compared. The oxygen consumptions of livers from starved and fed rats of both groups were similar. When comparisons were made on a wet liver weight basis, in both groups the livers from starved animals used significantly more oxygen than livers from fed animals. The livers from normal fed rats had respiratory quotients of 0·99. The livers from normal starved rats and fed and starved choline-deficient rats had significantly lower respiratory quotients of 0·75, 0·87 and 0·58 respectively. The livers from normal and choline-deficient starved rats produced more ketone bodies than the livers from fed rats. These findings suggested that normal fed livers were oxidizing largely carbohydrate; the low R.Q.'s found with choline-deficient livers were probably due to the oxidation of endogenous lipids.