ALTERATIONS IN ALVEOLAR MACROPHAGE TUMOR-NECROSIS-FACTOR (TNF) RESPONSE FOLLOWING HEMORRHAGIC-SHOCK

The purpose of this study was to determine if hemorrhagic shock alters the alveolar macrophage (MO) tumor necrosis factor (TNF) response to lipopolysaccharide (LPS) stimulation. New Zealand White rabbits underw ent hemorrhage and resuscitation. At 1, 2, 3, 5, and 7 days post-shock , both MOs and peripheral whole blood monocytes were incubated in vitr o with saline or Escherichia coli LPS. The supernatants were assayed f or TNF activity using the L929 bioassay. Alveolar MOs from hemorrhaged animals showed reduced TNF activity during the first 5 days post-hemo rrhage. Maximal depression of TNF activity was observed on days 3 and 5 post-hemorrhage (p < .05). In comparison, peripheral whole blood mon ocytes showed an increased TNF response on post-shock days 2 and 3. Th ese results suggest that hemorrhagic shock and resuscitation different ially affect TNF response in alveolar and peripheral blood MO populati ons.