Patent ID: 7927821

Claim:
A method of screening for a compound or its salt that alters the binding property or signal transduction between (1) a G protein-coupled receptor protein comprising the amino acid sequence represented by SEQ ID NO: 1 or an amino acid sequence having at least 95% homology to the amino acid sequence of SEQ ID NO: 1, or a salt thereof and (2) a ligand to the receptor protein or a salt thereof, the method comprising comparing the binding amount of the ligand or a salt thereof to said receptor protein or a salt thereof or the cell stimulating activities between the following two cases: (i) the case wherein the receptor protein or salt thereof is brought in contact with the ligand or a salt thereof; and (ii) the case wherein the receptor protein or salt thereof is brought in contact with the ligand or a salt thereof and a test compound; wherein the ligand is a compound represented by formula: wherein each of Ar 1 and Ar 2 independently represents optionally substituted aryl; R 1 is an optionally substituted hydrocarbon group; and each of R 2 and R 3 independently represents a hydrogen atom or an optionally substituted homo- or hetero-cyclic group, or a salt thereof; or the ligand is a compound represented by formula: wherein ring A is an optionally substituted benzene ring; each of R 4 and R 5 independently represents a hydrogen atom, an optionally substituted hydrocarbon group, an optionally substituted heterocyclic group or acyl; R 6 is an optionally substituted hydrocarbon group; and X represents —NR 7 — wherein R 7 represents a hydrogen atom, an optionally substituted hydrocarbon group or an optionally substituted heterocyclic group, —O— or —S—, or a salt thereof.