[Detection and quantification of lipoprotein (a) in atherosclerotic lesions of human aorta]

Lipoprotein(a) [Lp(a)] represents an independent risk factor for atherosclerotic disease. In the present study, the extent to which Lp(a) accumulated in normal and various degrees of atheromatous lesions and the distribution pattern of Lp(a) in these lesions have been studied in thoracic aorta from the autopsy tissues by means of immunohistochemistry, immunoelectronic microscopy, enzyme-linked immunosorbent assay and computer-assisted image processing. Lp(a) was found to be localized preferentially in lesion areas and had its own distribution pattern in each kind of lesion. Lp(a) associated primarily with extracellular matrix and was detected in only a small number of foamy cells. Apolipoprotein B was also detected, whose staining pattern was always found to be congruent with that of Lp(a). This suggests that the immunoreactivity of apoB is related to the presence of Lp(a) at least in part, since Lp(a) possesses apoB in addition to apo(a). It was concluded that both low density lipoprotein and lipoprotein(a) play an important role in the pathogenesis of atherosclerosis.