STUDIES ON THE CIRCULATORY CHANGES IN THE DOG PRODUCED BY ENDOTOXIN FROM GRAM-NEGATIVE MICROORGANISMS

Abstract

A clinical problem of increasing magnitude is the occurrence of hypotension in patients with bacteremia associated with the liberation of endotoxin from gram-negative microorganisms (1-3). Although the local vascular effects of endotoxin have been extensively studied in animals, particularly with reference to necrotizing effects on tumors (4, 5) and the Schwartzman reaction (6, 7), the hemodynamic alterations produced by these bacterial products remain unexplained. Endotoxins constitute a group of similar chemical substances identified as protein-polysaccharide complexes (8). In the course of a series of investigations reported elsewhere (9, 10), it was found that the pattern of the shock and the pathological changes in the gastrointestinal tract produced by the intravenous injection of endotoxins derived frotn Brucella melitensis, Escherichia coli, Serratia marcescens 1 and Salmonella typhosa 1