The course of ketosis and the activity of key enzymes of ketogenesis and XXXX -body utilization during development of the postnatal rat.

@entity73023 @entity29709 @entity9931 @entity6178 @entity2453
1. The highest blood concentrations of @entity6178 bodies were found at 5 days of age, after which time the concentration fell to reach the adult value by 30 days of age. 2. Both mitochondrial and cytoplasmic @entity2453 synthase activities were detected, with highest activities being found in the mitochondria at all stages of development. Activity of the mitochondrial enzyme increases rapidly immediately after birth, showing a maximum at 15 days of age, thereafter falling to adult values. The cytoplasmic enzyme, on the other hand, increased steadily in activity after birth to reach a maximum at 40 days of age, after which time activity fell to adult values. 3. Both mitochondrial and cytoplasmic @entity29709 thiolase activities were detected, with the mitochondrial enzyme having considerably higher activities at all stages of development. The developmental patterns for both enzymes were very similar to those for the corresponding @entity2453 synthases. 4. The activity of heart @entity29709 transferase remains constant from late foetal life until the end of the suckling period, after which time there is a gradual threefold increase in activity to reach the adult values. The activity of brain @entity73023 @entity9931 -transferase increases steadily after birth, reaching a maximum at 30 days of age, thereafter decreasing to adult values, which are similar to foetal activities. Although at all stages of development the specific activity of the heart enzyme is higher than that of brain, the total enzymic capacity of the brain is higher than that of the heart during the suckling period.
