Gestational alcoholism and fetal zinc accretion in Long-Evans rats

Liver alcohol dehydrogenase activity and ethanol levels during chronic ethanol intake in pregnant rats and their offspring

The effects of chronic alcohol intake on the ethanol levels in body fluids (blood, amniotic fluid, and fetal intragastric content), hepatic alcohol dehydrogenase (ADH) activity, isoenzyme distribution, and hepatic zinc levels were studied in pregnant rats at term (19 and 21 days), in their offspring at fetal, perinatal, and weaned stages, and in adult virgin rats. Three experimental groups were studied: 1) the alcohol group received ethanol in drinking water (from 10% to 25% over 2 months), 2) the fibre diet group was undernourished on a hypocaloric diet, to assess the effects of malnutrition associated with chronic alcohol intake, and 3) the control group received no alcohol and normal diet. A gradient of increasing ethanol concentrations was found in fetal blood, amniotic fluid, and fetal intragastric contents with respect to maternal blood. A decrease in ADH activity was found in alcohol-consuming pregnant rats compared to controls. This was related neither to liver ADH isoenzyme distribution nor to changes in hepatic zinc levels. Chronic alcohol consumption in pregnant rats produced high ethanol accumulation in fetal fluids and changes in the liver ADH activity depending on the physiological situation (pregnancy, development, virgin state).

Purification and characterization of a low molecular weight zinc binding protein from human placenta

A low molecular weight, native zinc binding, cytosolic protein (LMZP) has been isolated, purified and characterized from human normal term placenta. Gel filtration of heat treated placental cytosol after sequential acetone precipitation (80% ppt) revealed a major zinc binding protein in the range of low molecular weight. This partially purified zinc binding fraction was further fractionated on DEAE-Sephadex A-25. The zinc was eluted in one of the three peak fractions. Further, the purity of zinc binding protein was confirmed on fast protein liquid chromatography (FPLC). The purified placental LMZP was homogenous on SDS-polyacrylamide gel electrophoresis with a single band. Ultraviolet (UV) spectrum of LMZP showed an absorption maximum at 257 nm which disappeared at pH 2. Molecular weight of LMZP as determined by gel chromatography, SDS-polyacrylamide gel electrophoresis and amino acid analysis was 6 kDa. It was calculated that 1 g atom of zinc was bound to 1 mole of the LMZP. Unlike in classical metallothionein, the amino acid composition of placental LMZP revealed the presence of aromatic amino acids, lower content of cysteine and higher content of histidine, glutamic acid and aspartic acid (10, 9 and 5 residues/mole, respectively).