Alterations of surface charges of plasma lipoproteins in ischemic heart disease.

For a charged and an uncharged long chain spin probe the partition between the aqueous phase and the lipoproteins LDL, HDL2 and HDL3 was measured by use of ESR spectroscopy. The partition coefficients were compared for lipoproteins from normal donors and lipoproteins from patients with ischemic heart disease. The partition coefficients of the uncharged spin probe are not different. However, the charged spin probe has a significantly different partition for LDL and HDL3. This difference results from changes in the surface charge. Patients with ischemic heart disease have LDL which is more electropositively charged and HDL3 is more electronegatively charged compared to the corresponding lipoproteins of normal subjects. The surface charge of HDL2 is not changed. The results are discussed in the light of current concepts of the pathogenesis of atherosclerosis.