Lipid peroxidation and lung ultrastructural changes in an experimental model of leukocyte-mediated pulmonary injury.
The aim of this study was to study ultrastructural changes and lipid peroxidation in rabbits lung after massive complement activation and leukocyte aggregation. A prolonged and massive leukocyte activation was induced by intraperitoneal inoculation of zymosan suspected in paraffin. Fifteen animals (group 3) were given 0.6 g/kg of zymosan, 22 animals (group 2) received 1 g/kg, and 11 rabbits (group 1) were treated with paraffin alone and served as controls. An acute mortality rate of 40% was observed in group 3 and of 68% in group 2. Surviving animals were studied for 10 days. In these animals a marked decrease in circulating granulocytes and a progressive decline in arterial PO2 were recorded (PO2 on day 10 in group 2 animals was 51.94 +/- 4.26, p less than 0.01). Microscopic and ultrastructural evaluation revealed sequestration of granulocytes in the pulmonary microvasculature. Studies of lung homogenates demonstrated increased levels of lipid peroxide derivative malondialdehyde (group 2 rabbits, 1624 +/- 638; group 1, 795 +/- 57 pm/mg pt, p less than .001) and decreased levels of the tissue antioxidant alpha-tocopherol. The results of this study are compatible with the hypothesis of leukocyte-mediated injury through production of oxygen radicals.
Borrelli
E
E
Institute of Thoracic and Cardiovascular Surgery, University of Siena, Italy.
Giomarelli
P
P
Chiara
O
O
Casini
A
A
Betti
S
S
Sabatini
L
L
Lorenzini
L
L
Grossi
A
A
D000818:Animals; D002449:Cell Aggregation; D003167:Complement Activation; D004195:Disease Models, Animal; D007962:Leukocytes / Q000276:immunology*; D015227:Lipid Peroxidation; D008171:Lung Diseases / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D008315:Malondialdehyde / Q000032:analysis; D011817:Rabbits; D014810:Vitamin E / Q000032:analysis
D014810:Vitamin E; D008315:Malondialdehyde