| This thesis explored two aspects of lipoprotein(a). The first was the role of ethnicity in the association between properties of lipoprotein(a) and atherosclerosis and the second was metabolic properties of lipoprotein(a).; A significant association was found between elevated levels of lipoprotein(a) particles with small apo(a) isoforms, in men independent of ethnicity, with coronary artery disease in a case-control study and with carotid atherosclerosis in a random stroke-free population-based sample. These are the first studies demonstrating a significant association between lipoprotein(a) and coronary artery disease in African Americans. These findings suggest that the absence of association between lipoprotein(a) and coronary artery disease in African Americans in previous studies was not due to a difference in the atherogenicity of Lipoprotein(a) across race/ethnicity, but a consequence of race/ethnicity differences in the distribution of lipoprotein(a) levels across apo(a) sizes.; The metabolic study, which used a primed constant infusion of stable isotopes, demonstrated in six normolipidemic subjects with high lipoprotein(a) levels that low density lipoprotein apoB does not seem to be a major direct precursor for lipoprotein(a) apo B. Furthermore, the data are consistent with the hypothesis that lipoprotein(a) apo B and lipoprotein(a) apo(a) have similar metabolic pathways. |
