Effect of antibody-mediated neutropenia on the cardiopulmonary response to endotoxemia.
An ovine anti-neutrophil antibody has been produced by immunizing rabbits with purified sheep neutrophils. Serial intraarterial infusions of anti-neutrophil antibody in awake instrumented sheep produced selective and profound neutropenia. Intravascular infusion of endotoxin (Escherichia coli, 1.5 micrograms/kg/30 min) resulted in significant and equivalent increases in pulmonary artery pressure, peripheral vascular resistance, and protein-rich pulmonary lymph flow in an endotoxin group (n = 9) and a depletion + endotoxin group (n = 4). Changes in cardiopulmonary parameters were most pronounced 2 to 8 hr after endotoxin administration in both groups. Cardiac index (CI) showed a precipitous and transient fall in both experimental groups at 0.5 to 1 hr after endotoxin infusion; however, by 8 hr CI rose significantly in the endotoxin group, while it remained unchanged in the depletion + endotoxin group. A significant rise in the peripheral neutrophil count was associated with the increase in CI in the endotoxin group. Plasma and pulmonary lymph levels of thromboxane-B2 were unchanged during the depletion period with a significant increase 1 hr after endotoxin infusion. In this study questions arise regarding the exclusive role of circulating neutrophils in the microvascular permeability changes seen in sepsis-mediated adult respiratory distress syndrome.
Basadre
J O
JO
Department of Surgery, University of Texas Medical Branch, Galveston 77550.
Singh
H
H
Herndon
D N
DN
Stothert
J
J
Traber
L D
LD
Horn
K
K
LeBlanc
K
K
Flynn
J T
JT
Traber
D L
DL
D000818:Animals; D000906:Antibodies; D004731:Endotoxins; D005260:Female; D006439:Hemodynamics; D008196:Lymph / Q000378:metabolism; D009503:Neutropenia / Q000378:metabolism / Q000503:physiopathology; D009504:Neutrophils / Q000276:immunology / Q000502:physiology*; D011506:Proteins / Q000378:metabolism; D011652:Pulmonary Circulation; D012756:Sheep; D013929:Thromboxane B2 / Q000378:metabolism
D000906:Antibodies; D004731:Endotoxins; D011506:Proteins; D013929:Thromboxane B2