TY - JOUR T1 - Abnormal responses to endothelial agonists in Raynaud's phenomenon and scleroderma. JF - The Journal of Rheumatology JO - J Rheumatol SP - 119 LP - 121 VL - 28 IS - 1 AU - R R Freedman AU - R Girgis AU - M D Mayes Y1 - 2001/01/01 UR - http://www.jrheum.org/content/28/1/119.abstract N2 - OBJECTIVE: To further specify the site of vascular dysfunction in patients with Raynaud's phenomenon (RP) and scleroderma. METHODS: Ten patients with RP and scleroderma and 11 healthy control subjects received brachial artery infusions of sodium nitroprusside, an endothelium independent vasodilator, bradykinin, and substance P while bilateral finger blood flow was measured with venous occlusion plethysmography. RESULTS: Both groups showed vasodilation to sodium nitroprusside. However, in response to the endothelium dependent compounds bradykinin and substance P, the controls showed vasodilation, whereas the patients showed vasoconstriction. CONCLUSION: The vascular defect in RP and scleroderma does not lie at the site of the muscarinic receptor, but possibly in a distal signaling mechanism. ER -