KLK4 and peritonitis: In order to analyze the effects of SM on another independent model of TLR4-mediated inflammatory response in vivo, we studied its impact on carrageenan-induced peritonitis, the development of which consists of several phases, including not only an increase in the levels of pro-inflammatory cytokines, but also the activation of histamine/kallikrein/kinin and prostaglandin/COX-2 systems and the generation of neutrophil-derived reactive oxygen species, nitric oxide, and peroxynitrite [155,156,157].