The pharmacological properties of bradykinin (BK) receptors were characterized in canine cultured corneal epithelial cells (CECs) using [3H]-BK as a radioligand. Analysis of binding isotherms gave an apparent equilibrium dissociation constant of 0.34 ± 0.07 nM and a maximum receptor density of 179 ± 23 fmol/mg protein. Neither a B1 receptor-selective agonist (des-Arg9-BK) nor antagonist ([Leu8, des-Arg9]-BK) significantly inhibited [3H]-BK binding to CECs, thus excluding the presence of B1 receptors in canine CECs. The specific binding of [3H]-BK to CECs was inhibited by B2 receptor-selective agonists (BK and kallidin) and antagonists (Hoe 140 and [D-Arg⁰, Hyp3, Thi5,8, D-Phe7]-BK), with a best fit using a one-binding-site model. The order of potency for the inhibition of [3H]-BK binding was BK = Hoe 140 > kallidin > [D-Arg⁰, Hyp3, Thi5,8, D-Phe7]-BK. Stimulation of CECs by BK produced a concentration-dependent accumulation of inositol phosphates (IP) and an initial transient peak of intracellular Ca2+. B2 receptor-selective antagonist ([D-Arg⁰, Hyp3, Thi5,8, D-Phe7]-BK) significantly antagonized the BK-induced responses with dissociation constants of 6.0–6.1. Pretreatment of CECs with pertussis toxin (PTX) or cholera toxin did not alter the BK-induced IP accumulation. Incubation of CECs in the absence of external Ca2+ led to a significant attenuation of the IP accumulation induced by BK. These results demonstrate that BK directly stimulates phospholipase C-mediated signal transduction through BK B2 receptors via a PTX-insensitive G protein in canine CECs. This effect may function as the transducing mechanism for BK-mediated cellular responses.