Endotoxin designates the relatively homogenous group of toxic substances which exist as polysaccharide protein lipid complexes in Gram-negative microorganisms. Two important features of these substances are their biologic potency and their ubiquity as contaminants. The active agent in fever or nonspecific protein therapy is endotoxin.
The potent biologic effects1 of these substances can be divided into nonspecific toxic actions of all endotoxins and specific immunologic effects of each strain. The toxic effects, typically biphasic, include fever production, profound vasomoter disturbances, alterations in the white cell and platelet counts, metabolic alterations, tumor necrosis, and the Shwartzman reaction. With repeated doses there is a rapid appearance of a state of nonspecific resistance or tolerance against further toxic effects.
In the normal rabbit eye a single parenteral administration of endotoxin produces an inflammation with a biphasic alteration in pressure.2,3 Tolerance to the ocular inflammation can be quickly developed by repeated administration.
LEVENE RZ, LONG R, LATESSA A. Further Ocular Effects of Endotoxin. Arch Ophthalmol. 1962;68(3):360-368. doi:10.1001/archopht.1962.00960030364011