Malate dehydrogenase (decarboxylating) (NADP) and α-glycerophosphate oxidase in the developing rat

The Effect of 3,5,3′-Triiodothyronine on Phosphoenolpyruvate Carboxykinase, Fatty Acid Synthetase and Malic Enzyme Activity of Liver and Brown Fat of Fetal and Neonatal Rats

“…It is apparent that T3 in brown fat raises the activity more in fe tuses and suckling animals than in animals in the weaning period: while in liver the oppo site is found, the activity being very low in the fetus and newborn and rising at the time of weaning when the effects of T3 become more obvious. This confirms the data re ported by llemon [14] some time ago.…”

“…Table IV shows that this differ ence persists in the suckling period where again only cortisone has an effect on brown fat FAS activity. Table V confirms the wellknown effect of T3 on brown fat weight [14]. Table VI illustrates the effect of T3 on ME in brown fat and liver.…”

“…It is also well established that T3 elevates the ac tivity of ME [14]. Table III shows that FAS is Control rats injected with vehicle only.…”

Influence of Early Weaning on the Activity of Several Enzymes in the Liver of Rat

“…a sudden change from high fat to high carbohydrate diet increased the activity o f all these studied enzymes. Their activities in control rats are in good agreement with values reported by Ballard and Hanson (2), Hemon (11,12), Hemon and Berbey (13) and Vernon and Walker (28,29). The increase o f hepatic ATP citrate lyase and malic enzyme activities is a regular consequence o f enhanced lipogenesis (14).…”

“…The impulse for this increase is very probably the change from high fat milk diet to high carbohydrate standard laboratory diet, the decrease o f blood lipids, the activation o f thyroid gland and changes o f sensitivity o f hepatic cells towards thyroid hormones. These results showed that early weaning modifies to the known picture o f physiological weaning to a great extent.The studies o f postnatal development o f mammalian liver have shown grad ual increases in the activity o f several enzymes in this organ, whereas no enzyme activity has been detected prenatally (2,3,12,31). These changes are in close relationship with changes in diet (3,28,29,31).…”