Relative roles of endothelial cell damage and platelet activation in primary Raynaud's phenomenon (RP) and RP secondary to systemic sclerosis

Objective : To evaluate the relative roles of endothelium and platelets in the pathogenesis of primary RP and RP secondary to SSc. Methods : Endothelial derived ET-1, t-PA, PAI-1, and platelet derived &#103 -TG, PDGF, TGF- &#103 were measured in 36 patients with primary RP, 14 patients with RP secondary to SSc and 30 age and sex matched controls. Results : A significative increase of ET-1, t-PA, PAI-1, TGF- &#103, and &#103 -TG were the most relevant changes in patients with RP secondary to SSc with respect to the controls. Less relevant increases of t-PA, PAI-1, PDGF, and &#103 -TG levels were observed in patients with primary RP vs controls. Conclusions : These data seem to confirm the involvement of endothelial cells and platelets in the pathogenesis of RP, with mild changes in primary RP and more relevant changes in RP secondary to SSc.