FR167344 free base is an orally active, nonpeptide antagonist of the bradykinin receptor B2, exhibiting high-affinity binding (IC50: 65 nM) and showing no binding affinity for the B1 receptor.

Bradykinin receptor B2:65 nM

FR167344 shows no stimulatory effects on PI hydrolysis. FR167344 inhibits the B2 receptor-mediated phosphatidylinositol (PI) hydrolysis and produces a concentration-dependent rightward shift in the dose-response curve to bradykinin, in competitive experiments using membranes prepared from Chinese hamster ovary cells expressing the bradykinin receptor subtypes. This shift is accompanied by a progressive reduction of maximal response. Estimated pA2 values for the antagonism of bradykinin-induced PI hydrolysis by FR167344 is 8.0 [1].

FR167344 (p.o.; 2h; carrageenin injection) inhibits carrageenin-induced paw oedema in rats (ID50: 2.7 mg/kg). FR167344 (p.o.) inhibits kaolin-induced writhing in mice (ID50: 2.8 mg/kg in 10 min writhing and 4.2 mg/kg in 15 min writhing). FR167344(p.o.) inhibits caerulein-induced pancreatic oedema (ID50: 13.8 mg/kg) and it also increases in amylase and lipase of blood samples (ID50: 10.3 and 7.4 mg/kg, respectively, in rats) [2].