Merck, P2297-5X10ML, Picrylsulfonic acid solution

Picrylsulfonic acid solution is a hapten, which can bind to tissue proteins and turn into an antigen. This leads to several immunologic responses. Colitis induced by a 2,4,6-trinitrobenzene sulfonic acid (TNBS) is a type of delayed hypersensitivity reaction to haptenized proteins. Leukotriene B4 (LTB4) and the monhydroxyl fatty acids 5-hydroxyeicosatetraenoic acid (5-HETE), 12-HETE, and 15-HETE are the major inflammatory mediators involved in this TNBS-induced colitis. Ethanol when used in high concentration act as a vehicle for the TNBS administration.