A Role for Platelet-Derived Growth Factor in Drug-Induced Chronic Ergotism?

Generalized vasoconstriction in chronic ergot poisoning is attributed both to the ergotamine activity on a-adrenergic receptors and to its direct action on vascular smooth muscle cells. The authors propose that endothelial wall, chronically damaged by ergot alkaloids, releases platelet-derived growth factor (PDGF), which contributes to vasoconstriction and promotes further arterial obstruction. Their hypothesis is supported by the increased PDGF activity found in plasma of a patient suffering from chronic ergotism. [ABSTRACT FROM AUTHOR]