Repositori URV

Identifier: TDX:427

Handle: https://hdl.handle.net/20.500.11797/TDX427

Authors:
Simó Sisó, Josep Maria

Abstract:
Lipoprotein (a) is a class of lipoprotein particles resembling low density lipoprotein (LDL) in which apo B100 is covalently linked to a high polymorphic glycoprotein apolipoprotein termed apo(a). Although the physiological function of Lp(a) is unknown, numerous epidemiological studies have shown that a high plasma concentration of Lp(a) represent an independent risk factor for the development of coronary heart disease, however some confusing results in some of this studies has been reported. Apo(a) shares a high structural homology with plasminogen As plasminogen, apo(a) kringle domains contain Lysine Binding Site(s) (LBS) that interact with residues of lysine. Kringle IV10 of apo(a) is the primary LBS of Lp(a) and is associated with lesion formation on transgenic mice .The purpose of this study was · To examine de association of Lp(a) concentration, apo(a) size and Lp(a) lysine-binding site in patients with early onset heart diseases and age matched controls. · Search for mutations in the apo(a) kringle IV10 which could alter the LBS activity of Lp(a)· to investigate the decrease in Lp(a) values in samples from controls and patients with established cardiovascular disease that had been frozen for 5 years and to analyze the relationship between such decrease and the number of kringle IV repeats in the smallest and largest isoforms.Methods Blood was obtained from survivors of premature myocardial infarction and age matched controls, plasma was measured by immunoturbidimetry , apo(a) genotype was determined by pulsed-field gel electrophoresis, apo(a) phenotype by gel electrophoresis and immunoblotting, LBS activity was measured by a quantitative LBS-Lp(a) immunoassay as previously described. Detection of mutations and polymorphisms in kringle IV10 was revealed