The inflammation model of the isolated hemoperfused bovine uterus was used to introduce a new in vitro model for the investigation of anti-inflammatory substances. As previous studies demonstrated both an increase in PGE2 synthesis and an up-regulation of COX-2 and iNOS mRNA by ischemia-reperfusion injury in the model (Braun and Kietzmann, 2004), inhibitory effects of the glucocorticoid dexamethasone, the NSAID flunixin and the selective COX-2 inhibitor DFU (5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)-phenyl-2-(5H)-furanone) were studied. All substances caused a significant decrease in tissue PGE2 production, while none induced down-regulation of COX-2 mRNA. A slight decrease in the mRNA level of iNOS was observed after 300 minutes of perfusion with dexamethasone-supplemented perfusion medium. In conclusion, the suitability of the isolated hemoperfused bovine uterus for the investigation of anti-inflammatory substances, especially regarding their COX-2 selectivity, was demonstrated. Use of the isolated hemoperfused bovine uterus in pharmacological research and drug screening may contribute to a reduction of animal testing.