抄録
Plasma lipids in cord blood drawn from 49 normal newborns were determined. Maternal plasma obtained shortly before the delivery were also analyzed. Sixty-two healthy adults (28 males and 34 females) aged 20 to 39 were adopted as control subjects.
Total cholesterol (TC), triglyceride, phospholipids, HDL-cholesterol (HDL-Ch), and HDL-phospholipids in cord blood were 72±20.3mg/dl, 69±16.0mg/dl, 134±37.0mg/dl, 39±11.6mg/dl, and 82±17.9mg/dl, respectively. All these values were significantly lower than the control values. HDL-Ch/TC ratio in cord blood was 0.57±0.16 and it was significantly larger as compared with control value (0.36±0.10). Cord blood HDL-Ch level in Japanese might be ranked relatively high among reported values in various countries. More prominent feature was that HDL-Ch/TC ratio was much larger than the values reported in western countries. Therefore, it can be said that, at least in neonatal period, Japanese has relatively smaller amount of LDL-cholesterol than western people.
Maternal administration of prostaglandin E2 (PG) caused the difference in HDL-Ch concentration. Cord blood HDL-Ch in PG-treated group was significantly lower than that in non-treated group.
Percent ester cholesterol in HDL (HDL-CE) was evaluated measuring the free cholesterol content of HDL. The values in cord blood and maternal blood were 72±6.1% and 80±4.1%, respectively. HDL-CE in cord blood was significantly lower as compared with the control value (81±4.9%). Inverse relationship was observed between cord blood HDL-CE and birth weight. These results may indicate the possibility of low cholesterol-removing capacity of HDL in newborn infants. Our suggestion is that the rate of cholesterol-removal from peripheral tissues may be low in newborns actively utilizing cholesterol. The larger the birth weight is, the lower the rate might be.
Neonatal HDL-Ch and HDL-CE correlated directly with each corresponding value in maternal blood. Placental transfer of HDL as intact particles might occur as suggested before (Tamai et al., 1979).
