Jiang et al. studied pre-injury dexmedetomidine (2.5 and 5 μg/kg/h) effects in an ischaemia (hilar occlusion) model of ALI in rats, finding dexmedetomidine reduced lung injury scores and inflammatory markers (MPO, TNFα, IL-6, TLR4, MyD88, Phospho-JNK, and Phospho-ERK); yohimbine partially reversed effects on some injury markers [18]. This evidence concerns the gene TLR4 and acute respiratory distress syndrome.