Serum endothelin in patients with Raynaud syndrome before and following cold provocation

: To determine wether there is a pathogenetic effect of endothelin (ET) in vasoconstriction in Raynaud's phenomenon, plasma-endothelin and it's association to extent of vasoconstriction was measured before and after digital cooling. Only in cases with massive vasoconstriction ET rose significantly after cooling. In conclusion ET seems to be involved in the pathogenesis of RS, whereas the exact pathomechanism remains unclear.