Effect of fulvine on pulmonary arteries and veins of the rat.

Wagenvoort, C. A., Wagenvoort, N., and Dijk, H. J. (1974). Thorax, 29, 522-529. Effect of fulvine on pulnonary arteries and veins of the rat. Fulvine, one of the pyrrolizidine alkaloids from the Crotalaria group, was administered to rats in a single dose. Vasoconstriction and medial hypertrophy of pulmonary arteries and right ventricular hypertrophy developed gradually, starting after one week. Smooth muscle fibres developed in the arterial adventitia. Fibrinoid necrosis and arteritis of these arteries were common. In addition, however, changes were observed in pulmonary veins and venules which showed thickening of their walls by constriction, proliferation of muscle fibres, and increase of collagen, leading to luminal occlusion. Apparently fulvine is angiotoxic not only for pulmonary arteries but also for pulmonary veins. This detracts from the usefulness of fulvine in the experimental production of pulmonary arterial hypertension.