PATHOPHYSIOLOGY OF RAYNAUDS-PHENOMENON

Despite over a century of investigation, the pathophysiology of Raynau d's phenomenon remains an enigma. The two main theories of the cause o f digital artery vasospasm are increased activity of the sympathetic n ervous system and a local fault in the digital vasculature. An increas ed sensitivity and/or concentration of alpha-2 adrenoreceptors is sugg ested. The activation of serotoninergic receptors may play a role in t he maintenance of vasospasm. The recently discovered increase in the v asoconstrictive peptide endothelin-1 and the quantitative deficit in t he potent vasodilating calcitonin gene-related peptide may lead to a b etter understanding of vasospasm mechanisms and open the field for new therapeutical approaches to Raynaud's phenomenon.