[Analysis of mechanism of lung edema in E. coli injected septic rat model--in relation to tumor necrosis factor (TNF) produced from liver, spleen, and alveolar macrophages].

After injection of live E. coli, TNF in blood and culture supernatant of the isolated macrophages from the lung, liver, and spleen, were measured, and possible relationship between their TNF levels and lung edema was examined. The blood TNF activity increased significantly until 3h after the injection in the lethal group (p less than 0.01). The TNF activity of alveolar macrophages showed no changes even in the lethal group. The TNF activities of the liver and spleen macrophages decreased significantly in the lethal group (p less than 0.01-0.05), while those in the sublethal group that didn't induce lung edema and showed no significant decrease. The blood leukocyte count decreased until 6h after the injection in the both sublethal and lethal groups, but there was no significant difference between the two groups. The lung weight difference of the lethal group was significantly higher than that in the control group 12h after injection (p less than 0.05). Therefore, the elevated blood TNF activities in our study may be not elicited from alveolar macrophages but mainly from liver and spleen macrophages. There may be a relationship between the lung edema and the elevated blood TNF activity in the lethal groups.