Effect of neonatal thyroidectomy on enzymes in subcellular fractions of rat brain

Growth, enzymes and hormonal changes in offspring of alcohol-fed rats

Consumption of ethanol by rats during pregnancy reduces the body and brain weight of their fetuses and pups. The reduction is greater if the offspring are kept with their alcohol-fed mothers rather than with control surrogate mothers during lactation. The activity of several enzymes of the neuronal cell membranes (Na+, K+-ATPase, Ca2+-ATPase, acetylcholinesterase, 5'-nucleotidase) is also reduced. This decrease in enzyme activity may be related to the decrease in neuronal development and could produce profound alterations in brain function. Altered hypothalamic-hypophysial function may be partly responsible for developmental anomalies found in the fetal alcohol syndrome. The levels of plasma luteinizing hormone are lower in pups exposed prenatally to ethanol, and prolactin levels are much higher. Concentrations of ethanol were essentially the same in maternal blood and in the fetus. Acetaldehyde levels in the placenta, amniotic fluid and the remaining fetal tissue at days 15 and 19 of gestation were about 40-50% of those in maternal blood. Acetaldehyde may be important in the pathogenesis of the fetal alcohol syndrome.

Effects of prenatal and postnatal exposure of rats to alcohol: changes in (Na+-K+) ATPase

Maternal ethanol consumption produces a reduction in postnatal growth. We have studied especially changes of liver and brain. This reduction is more marked if the alcoholic offspring are maintained with their biological mothers than if they are kept with surrogate mothers. Rats exposed prenatally to alcohol show a marked accumulation of fat in the liver and a significant proliferation of liver endoplasmic reticulum. No change in the postnatal development of liver alcohol (ADH) and acetaldehyde dehydrogenases (ALDH) (high and low Km) is observed in offspring from alcoholic mothers, with the exception of slightly higher ALDH (low Km) for the offspring that remain with alcoholic mothers. The postnatal development of the liver (Na+-K+) ATPase is also similar in control and alcoholic groups. However, in the case of the enzyme from the brain, a lower ATPase activity is observed in the group derived from alcoholic mothers. Interestingly, at 20 days of postnatal period, an induction of the ATPase (from liver and brain) was observed when the group of offspring from alcoholic mothers were kept on an alcohol diet.

Neonatal hypothyroidism and early undernutrition in the rat: defective maturation of structural membrane components in the central nervous system

The action of neonatal hypothyroidism and early undernutrition on the lipid and protein composition, as well as, on the activity of 2'3' cyclic nucleotide 3' phosphohydrolase was studied in different subcellular fractions isolated from 20 day old hypothyroid and undernourished rats. Based on protein content, a marked decrease (70%) in the recovery of myelin was observed in both experimental conditions. The lipid composition of myelin in both groups was, however, different; while cholesterol, total phospholipids, and total galactolipids decreased in a similar fashion in the two situations; sulfatides and plasmalogens were much more affected in hypothyroid rats.