We analyzed if genomic responses of adult zebrafish tissues can reproduce the mammalian known inflammatory process induced by acute endotoxin stress. Although the strength of the inflammatory process was influenced by tissue nature, gene regulation was well conserved across evolution and zebrafish genomic responses highly correlated with mammals’ inflammatory reactions after lipopolysaccharide stimulation. Overall design: 10 μg of pure LPS (Sigma) or PBS was intraperitoneally injected to healthy fish and livers, kidneys and muscle were sampled and pooled at 3 hours post injection to analyse the inflammatoy response.