<p>The object is to identify a receptor for ADNF to elucidate a specific signaling pathway of the anti-ALS activity of ADNF, and to provide a screening system for identifying a compound capable of binding to the ADNF receptor or a compound capable of inhibiting or enhancing the binding between ADNF and the ADNF receptor or the like. Disclosed is an ADNF receptor comprising a polypeptide having any one of the following amino acid sequences (1) to (3): (1) the amino acid sequence depicted in SEQ ID NO:2 or 3; (2) an amino acid sequence having the deletion, substitution or insertion of one or several amino acid residues in the amino acid sequence depicted in SEQ ID NO:2 or 3; and (3) an amino acid sequence having a 70% or more homology with the amino acid sequence depicted in SEQ ID NO:2 or 3.</p>
