EFFECT OF HEPATOCYTES FROM NORMAL OR ENDOTOXIN-TREATED ANIMALS ON THEPRODUCTION OF TUMOR-NECROSIS-FACTOR, INTERLEUKIN-6, AND PROSTAGLANDIN-E(2) BY MACROPHAGES INCUBATED IN-VITRO WITH VARIOUS FATTY-ACIDS

Objective: To find out if the in vitro production of tumour necrosis f actor (TNF), interleukin 6 (IL-6) and prostaglandin E(2) (PGE(2)) by m acrophages (P3888D(1)) were influenced by the addition to the culture media of hepatocytes from normal guinea pigs and from guinea pigs afte r infusion with endotoxin with and without fatty acids. Design: Labora tory experiment. Setting: University hospital, United States Material: 12 male Hartley guinea pigs. Main outcome measures: Concentrations of TNF-alpha, IL-6, and PGE(2). Results: Hepatocytes inhibited the produ ction of TNF by macrophages. Those from animals pretreated with endoto xin caused a large increase in the production of PGE(2) and affected t he production of IL-6 only in the presence of fatty acids. Fatty acids differed from each other in their effects on production of TNF-alpha and PGE(2), but had no effect on the production of IL-6. Conclusion: T hese results support the concept that hepatocytes and macrophages may interact in vivo, and this interaction may be influenced both by fatty acids that arise from lipid metabolism and from endotoxin present dur ing sepsis and translocation.