Lesions indistinguishable from those of the generalized Shwartzman reaction occured in rabbits when a single intravenous injection of Gram-negative bacterial endotoxin was accompanied, or followed, by an injection of one of the following synthetic, heparin-like, acidic polymers-sodium polyanethol sulfonate, dextran sulfate, or sodium polyvinyl alcohol sulfonate.
These reactions were produced by doses of polymer or of endotoxin which were without demonstrable effect when given singly.
Heparin, in those similar to those previously shown to protect rabbits against the lesions of the generalized Shwartzman reaction, prevented the reaction to the combined injection of endotoxin and acidic polymers.
Nitrogen mustard, which was previously shown to prevent the lesions of the generalized Shwartzman reaction from occurring after two intravenous injections of endotoxin, had no protective action against the lesions produced by the combined injection of endotoxin and polymer.
Cortisone did not affect the reaction to endotoxin and polymer.
The role of fibrinogen in the reaction under study is discussed in the paper which follows.