INTRAVASCULAR ACTIVATION OF THE CLOTTING SYSTEM WITH PHOSPHOLIPIDS. PRODUCTION OF THE GENERALIZED SHWARTZMAN REACTION WITH PLATELET FACTOR 3.

Abstract

Shwartzman reaction (GSR )-is observed in rabbits after two properly spaced intravenous injections of endotoxin derived from gram-negative bacteria and is characterized by profound collapse and hemorrhagic diathesis. Marked changes in the blood clotting mechanism in animals undergoing GSR have been described’6’30’35 and resemble those observed when blood clots in vitro. The platelets which remain in the circulation of these animals are altered both in number and in their specific procoagulant effects; the activities of both platelet factor 1 (adsorbed Ac-G) and of platelet factor 3 (phospholipid) are greatly impaired.�’36 Morphologically, the reaction is characterized by a generalized intravascular deposition of fibnin. Bilateral renal cortical necrosis with fibnin-thrombi in the glomerular capillaries is observed in animals that survive long enough to develop this lesion. The present work deals with the morphologic and coagulative changes produced by infusing phospholipid having platelet factor 3 activity, or soya bean phospholipid (Inosithin), in rabbits previously given intravenous thorotrast with the intent of blocking the reticuloendothelial system. The alterations described were indistinguishable from those observed in the classical GSR produced in rabbits with two intravenous injections of endotoxin.