The effects of interleukin-10 in hemorrhagic shock

Background Interleukin-10 (IL-10) counteracts the effects of the proinflamm atory cytokines interleukin-l (IL-1), interleukin-6 (IL-6), and tumor necro sis factor (TNF). Experimental data suggest that inhibition of these proinf lammatory cytokines improves outcome in sepsis, endotoxemia, necrotizing pa ncreatitis, and other severe inflammatory states. We hypothesized that the administration of IL-10 would attenuate the release of proinflammatory cyto kines after severe hemorrhagic shock. Methods. To test our hypothesis, male Sprague-Dawley rats (N = 20) were div ided into control and experimental groups. We induced hemorrhagic shock by removing a sufficient quantity of blood to maintain a mean arterial pressur e of 50 mm Hg or less for 120 min. The animals were then resuscitated with shed blood and an equal volume of 0.9% saline. The experimental group recei ved 10,000 units of IL-10 at the initiation of shock. Serum IL-1, IL-6, TNF , and lactate were measured at baseline, after 120 min of shock, and 60 min after resuscitation. The rats were followed for 72 h to calculate survival . Results. Similar levels of hypoperfusion were obtained in both groups as de monstrated by lactate levels and amount of shed blood. The survival rate (7 0%) was the same in both groups. Serum levels of IL-l and IL-6 were not sig nificantly different between the two groups, although there was a trend tow ard IL-6 suppression. TNF, however, was significantly lower in the IL-10-tr eated group at the end of shock (Wilcoxon test, P < 0.025). Conclusion. Administration of IL-10 suppresses the TNF surge observed after severe hemorrhagic shock. (C) 2000 Academic Press.