TRPV1 and Crohn ileitis: The fact that LTB4 is an endogenous TRPV1 agonist [16] coupled with our demonstration that inhibition of 5-LO inhibited both toxin A-induced ileal LTB4 levels and toxin A- but not LTB4-induced ileitis led us to propose that C. difficile toxin A causes ileitis by stimulating mucosal LTB4 production that subsequently initiates neurogenic inflammation mediated by TRPV1.