Short-term effect of oophorectomy on lipoprotein metabolism.

The influence of steroid hormones on lipoprotein metabolism has been investigated in menstruating women undergoing oophorectomy; indeed, by this procedure, it is possible to alter selectively the secretion of the hormones and thus to determine the influence of their withdrawal on blood lipids. Within 3 months of surgery we observed significant rapid changes in cholesterol levels of total and HDL-bound components (early decrease and subsequent increase) without alteration of the triglyceride component of the lipoproteins. Similar biphasic changes were observed for the apolipoproteins A and B, determined by immunological methods. These results are suggestive of an action of sex hormones on the lipoprotein metabolism, both on the lipid and the protein moieties. They can be explained by a primary action of the hormones on the apolipoprotein metabolism and a secondary apoprotein-mediated effect on the lipid component of the lipoproteins.