This is supported by results obtained in different experimental models of inflammation including hepatic ischaemia-reperfusion, colitis, atopic dermatitis, in which H4R antagonists (JNJ7777120, JNJ10191584, thioperamide) produce anti-inflammatory effects with reduced neutrophil recruitment and release of cytokines, improving the outcome of the pathology.17,18 In some of these models H4R antagonists produce the same phenotype observed in H4R knockout mice. This evidence concerns the gene HRH4 and colitis.