The association of platelet-derived growth factor receptor expression, plaque morphology and histological features with symptoms in carotid atherosclerosis

Abstract

Platelet-derived growth factor may influence smooth muscle cell migration and proliferation and, therefore, carotid plaque composition and stenosis. Platelet-derived growth factor receptor expression and histological features were compared in carotid plaques from symptomatic and asymptomatic patients. Immunocytochemistry and histology determined platelet-derived growth factor- α and - β receptor expression, white blood cell infiltration, smooth muscle cell, elastin, cholesterol, collagen and intraplaque haemorrhage in carotid artery plaques removed at surgery or the post-mortem. Plaques with >70% stenosis from asymptomatic ( n=10) and symptomatic patients ( n=27) had higher expression of platelet-derived growth factor and β receptors and higher scores for macrophages and intraplaque haemorrhage than plaques with <70% stenosis from asymptomatic patients ( n=33). Plaques with >70% stenosis from symptomatic patients had significantly lower α receptor expression than plaques with >70% stenosis from asymptomatic patients. The reduction of α receptor expression, which may inhibit smooth muscle cell migration, suggests that differential expression of platelet-derived growth factor receptor subunits in plaques may be related to symptoms.