The Association of Platelet-Derived Growth Factor Receptor Expression, Plaque Morphology and Histological Features with Symptoms in Carotid Atherosclerosis

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.