A comparative analysis of the biochemical and physiological role of the maternal and amniotic environs in normal and dimethyl-sulfoxide-induced changes in macro-and micromolecules of the Long-Evans rat during fetalogenesis, 1976

A sequential study was carried out on maternal serum, fetal serum, and amniotic fluid from 13-1/2 - 20-1/2 days of gestation. This study was conducted to determine the regulatory role macromolecules such as serum-like proteins in amniotic fluids played in homeostasis during fetalogenesis. The total protein concentration in maternal serum fluctuates throughout pregnancy. From 13-1/2 to 18-1/2 days of gestation the total protein concentration exceeds that of non-pregnant rat serum. As gestation advances total protein of amniotic fluid and fetal serum also increases. The total protein of the amniotic fluid increases from 0.095 g/100 ml on 13-1/2 days of gestation to a mean high of 0.25 g/100 ml on 20-1/2 days of gestation. The total protein of fetal serum in 13-1/2-day fetuses showed a mean of 0.403 g/100 ml. The mean total protein in fetal rat serum increases to 2.4 g/100 ml by day 20-1/2. Albumin fractions in fetal serum and amniotic fluid represent more than 60% of the total protein, Densitometric scans show that as many as 6 bands can be identified in the amniotic fluid and fetal serum using Cyanogum-41 (polyacrylamide) gel electrophoresis. Large amounts of prealbumin are present during most of the gestational periods in the amniotic fluid and fetal serum. The amniotic fluid and fetal serum are very similar. Sodium and potassium concentrations in the amniotic fluid and maternal serum are very similar for the same gestation days. Sodium and potassium concentrations in the fetal serum are greater than that of maternal serum and amniotic fluid for 13-1/2 - 20-1/2 days of gestation. When maternal rats are subjected to dimethylsulfoxide (DMSO) treatment, this apparent sequential change in blood serum and amniotic fluid protein profiles is abolished. Observable electrolyte changes in these compartmentalized fluids are also evident. Gravid female rats injected on 14-1/2 days with 75% DMSO (0.25 ml) show a decrease in the total protein of the maternal serum on 15-1/2 days