Some factors affecting carbohydrate metabolism in hepatic tissues of different growth rates

Aspects of carbohydrate metabolism, namely glycogen concentration, glucokinase activity, hexokinase activity, lactate and α‐glycerophosphate production, were compared with growth rate in regenerating liver and two transplantable hepatomas (5123‐D and 7777). Lactate production with glucose as substrate was greater with whole homogenates than with supernatant fractions for the hepatomas but the reverse was the case with control, sham‐operated and regenerating liver. Nicotinamide had a greater effect on lactate production by homogenates of normal and regenerating liver than with tumor homogenates. The effect of nicotinamide was correlated with the NAD glycohydrolase activity of homogenates and supernatant fractions of the different tissues. It was suggested that changes in carbohydrate metabolism in regenerating liver show some resemblance to those observed in hepatomas of similar growth rate but more marked changes may be seen in the tumor tissues.