Number of glucocorticoid receptors in lymphocytes and their sensitivity to hormone action.

The study demonstrated a decreased level of glucocorticoid receptors (GR) in peripheral blood lymphocytes from hypercholesterolemic subjects, and an elevated level in patients with acute myocardial infarction. In the lymphocytes with a high GR number, dexamethasone inhibited [3H]-thymidine and [3H]-acetate incorporation into DNA and cholesterol, respectively, in the same manner as in the control cells. On the other hand, a decreased GR number resulted in a less efficient dexamethasone inhibition of the incorporation of labeled compounds.

Reduced sensitivity of peripheral cells to glucocorticoids in hypercholesterolemia.

It has been found that lymphocytes of hypercholesterolemic (HCh) subjects are characterized by a reduced number of glucocorticoid receptors (GcR) as compared with the cells of normolipidemics (N). Addition of HCh-sera or very low density lipoproteins, or low density lipoproteins isolated both from HCh-sera and N-sera to cultured human skin fibroblasts brought about a fall in the number of GcR in the cells. High density lipoproteins had no effect on GcR level.

Interconversions of HDL subfractions in normolipidemic and hypoalphacholesterolemic sera incubated with fibroblasts and hepatoma cell line Hep-G2.

Gradient gel electrophoresis was used to study the changes in the HDL subfractional spectrum according to the particle size during their interaction with hepatoma Hep-G2 cells and human skin fibroblasts. Incubation of normolipidemic sera with Ch-loaded fibroblasts resulted in a drop in small particle (HDL3a' HDL3b, HDL3c) and, a rise in large particle (HDL2b, HDL2a) proportions. In contrast, incubation of the same sera with hepatoma cells caused a decrease in HDL2b proportion and a HDL3a release.

The effect of phospholipids on the activity of mitochondrial pyrophosphatases. Lipidized soluble mitochondrial pyrophosphatase: the coupling factor for oxidation and phosphorylation.

The effect of temperature on the hydrolase activity of mitochondrial pyrophosphatases, i.e. soluble (PPase I) and membrane (PPase II), has been studied.