[Lipid and lipoprotein metabolism in the pregnant rat]

The hyperlipemia of pregnancy consists primarily of an increase in triglycerides. In this study a comparison was made of the changes in the level of serum lipid concentration and the major lipoprotein subfraction in pregnant and non-pregnant SHR and Wistar rat. The results obtained were as follows. The serum triglyceride concentration is significantly high in the last period of pregnancy, i.e. 8.9 fold in Wistar rat and 13.0 fold in SHR. The atherogenic Index in the last period of pregnancy was 0.92 in Wistar rat and 2.54 in SHR. These figures show a 1.2 fold and a 3.4 fold increase over the non-pregnant level. Lipoprotein metabolism in pregnancy is characterized by an increase in cyromycrone and VLDL which is a major carrier of triglycerides. The amount of triglycerides in cyromicrone fraction was increased 9 times in Wistar rat and 64 times in SHR, and Triglycerides in VLDL fraction was not significantly different between Wistar rat and SHR during pregnancy. From the above results, SHR is a strain which easily manifests hyperlipemia and hyperlipoproteinemia during pregnancy when compared to the Wistar rat.