A substance is described which can prevent or treat a
disease associated with the
secretion of an acid. A
calcium receptor activator is the
active ingredient in a composition which promotes
bicarbonate secretion in a
gastrointestinal tract. Examples of the
calcium receptor activator include γ-Glu-X-Gly, wherein X represents an
amino acid or an
amino acid derivative, γ-Glu-Val-Y, wherein Y represents an
amino acid or an
amino acid derivative, γ-Glu-Ala, γ-Glu-Gly, γ-Glu-Cys, γ-Glu-Met, γ-Glu-Thr, γ-Glu-Val, γ-Glu-Orn, Asp-Gly, Cys-Gly, Cys-Met, Glu-Cys, Gly-Cys, Leu-Asp, γ-Glu-Met(O), γ-Glu-γ-Glu-Val, γ-Glu-Val-NH2, γ-Glu-Val-ol, γ-Glu-Ser, γ-Glu-Tau, γ-Glu-Cys(S-Me)(O), γ-Glu-Leu, γ-Glu-Ile, γ-Glu-t-Leu, and γ-Glu-Cys(S-Me).