The object is to analyze a TRPV1-binding protein for the purpose of controlling a pain or the protection activity of a gastric mucosa induced by TRPV1 and to achieve the regulation of the action of TRPV1. Disclosed are: a mutant EHD4 which has a mutation in at least one amino acid residue selected from amino acid residues corresponding to position-66, position-184 and position-225 in the amino acid sequence of a normal murine EHD4; and a gene encoding the mutant protein; a regulator of the activity of TRPV1, which comprises the mutant protein; and a pharmaceutical composition comprising EHD4, a substance capable of increasing the activity of EHD4 or a substance capable of inhibiting the activity of EHD4 and a pharmaceutically acceptable carrier.
REGULATOR OF CAPSAICIN RECEPTOR ACTIVITY AND PHARMACEUTICAL COMPOSITION USING THE SAME