Abstract

The serum β-lipoprotein, its bound protein and lipid were assayed by Burstein's method on 91maternal-fetal pairs, and 148 cases of non-pregnant women for comparison. The serum α-and β-lipoprotein cholesterols were also determined in parallel with the serum β-lipoprotein on the 18 meternal-fetal pairs by the combined method of paper electrophoresis and chemical analysis.
The results observed are as follows;
(1) The serum β-lipoprotein, its bound protein and lipid levels of the non-pregnant women are 267.8±94.4mg%. 233.7±7.14mg% and 48.4±15.8mg% respectively.
(2) The β-lipoprotein, its bound protein and lipid levels of the maternal serum are 516.7±99.2mg%, 427.5±83.7mg% and 94.7±19.0mg% respectively, while those values of the fetal serum are 125.3±28.1mg%, 102.6±25.0mg% and 22.5±4.1mg% respectively; the meternal levels being four times as much as the fetal levels.
(3) The total serum cholesterol (α-+β-lipoprotein-cholesterol) level is 195.7±48.2mg% on the maternal side and 68.2±22.4mg% on the fetal side; the former is three times as much as the latter, and the maternal level is almost 1.5 times higher, but the fetal level is less than one half of the normal value.
(4) The maternal and fetal serum α-lipoprotein -cholesterol levels are 44.5±20.7mg% and 20.5±11.5mg% respectively, the former being twice as much as the latter.
(5) The β-lipoprotein-cholesterols of the maternaland fetal serum are 151.5±26.9mg% and 44.7±28.9mg% respectively, the former still being more than three times as much as the latter.
(6)β-/α-lipoprotein-cholesterol ratio is 3.2±0.88 on the maternal side and 2.7±0.59 on the fetal side, the former being 1.2 times as high as the latter.
(7) The serum β-lipoprotein level parallels those of the serum α-and β-lipoprotein-cholesterols both on the maternal and fetal sides.
(8) The possible explanation concerning great difference between maternal and fetal serum βlipoprotein, α-and β-lipoprotein-cholesterol is discussed with regard to their placental transfer.