Species differences in effect of gram-negative endotoxin on circulation

Abstract

Studies were made in 5 monkeys, 7 rabbits, and 33 cats of the effect of gram-negative endotoxin on aortic, pulmonary artery (PAP), and portal venous (PVP) pressures; and on changes in weight of a short segment of intestine. Studies of blood pooling were also made in 12 cats. The responses in these species were compared with those previously observed in the dog. Although variable degrees of hypotension developed at one time or another in all animals following injection of endotoxin, the early precipitous hypotension that characteristically occurs in the dog was observed only in the cat. However, in this species the dramatic fall in pressure could be ascribed to pulmonary vascular constriction and acute right ventricular hypertension and failure, and not to splanchnic pooling. PAP also became elevated in the monkey and the rabbit, but usually was of lesser magnitude and did not appear to explain the development of the relatively late hypotension that occurred in these species. The absence of significant increases in gut weight and the minor increments in PVP in all animals indicate that in none of these species is hepatic vein constriction and splanchnic pooling a significant mechanism in producing early shock as it is in the dog. Pathologic gross and microscopic studies in the monkey and gross examinations in the other species supported this conclusion.

The pulmonary ultrastructure in septic shock

“…Kulda and others (Kuida et al, 1961) observed that the pr'mate lung was markedly affected by the administration of endotoxin. Reported pulmonary pathological alterationg have varied due to prominent species differences ob-L served In the reaction to endotoxin.…”

“…Differences have also been observed betwee,, experiments utilizing a single injection of endotoxhi and those involvIng the generalized Shwartzman phenomenon (Wong, 1962;McKay et al, 1966;Horn and Collins, 1968b). Abnormal pulmonary hemodynamics and morphology following a single injection of endotoxin In dogs have been reported (Kuida et al, 1961;Harrison et al, 1969). Pulmonary changes after endotoxin in rats or rabbits Include platelet'agglutination within pulmonary capillaries (Stetson, 1951;McKay et al, 1966), rupture of capillary walls (DePalma et al, 1967), fibrin deposition (McKay et al, 1966;DePalfra et al, 1967), clumps of polymorphonuclear leukocytes (Stetson, 1951;DePalma et al, 1967;Horn and Collins, 1968b), and polymorphonuclear leukocyte fragmentation withIn the lung capillaries (McKay et al, 1966;Horn and Collins, 1968b).…”

Effects of Bradykinin and Autonomic Nervous System Inhibition on Systemic and Regional Hemodynamics in the Unanesthetized Rhesus Monkey

“…Their methods, however, are 100-fold less sensitive than those presently in use in our laboratory and are inadequate to measure the levels of bradykinin spontaneously generated during endotoxemia. The dog clearly responds differently to acute endotoxemia than does the primate (22,23). In addition, the kinin-generating systems of the dog have different specificities than those of the primate (24).…”

Escherichia Coli Bacteremia in the Squirrel Monkey I. EFFECT OF COBRA VENOM FACTOR TREATMENT

“…Utilization of this cobra factor (CoF)1 made feasible in vivo studies of the influence of complement depletion on experimental gram-negative bacillary bacteremia. A subhuman primate was utilized to approximate human physiologic responses (22)(23)(24)(25)(26)(27)(28)(29)(30).…”