Objective. To examine the resistance to oxidation of low-density lipoproteins (LDL) from patients with systemic sclerosis (SSc) and primary Raynaud's phenomenon (RP) compared with healthy controls.Methods. Plasma LDL were isolated from patients with diffuse cutaneous and limited cutaneous SSc (dcSSc and IcSSc, respectively), patients with primary RP, and healthy control subjects. The lipoproteins were assessed for their resistance to oxidation in the presence of cupric ions, using spectrophotometric assays.Results. LDL from patients with dcSSc and lcSSc were more susceptible to oxidation than were those from healthy control subjects or patients with RP.Conclusion. Our findings suggest that free radicals may play a role in the pathology of SSc.

PTHrP reaches the maternal circulation during lactation in amounts which could produce a systemic effect.