| abstract |
The present invention provides an agent for preventionnand/or treatment of itching comprising a substance capable ofnsuppressing the function involved in signal transduction ofnGPR4 as an active ingredient. It also provides annitrogen-containing tricyclic compound represented by thenformula (I) or a quaternary ammonium salt thereof, or anpharmaceutically acceptable salt thereof;n n[wherein R 1 represents substituted or unsubstituted lowernalkyl, etc.; R 2 represents hydrogen, substituted ornunsubstituted lower alkyl, etc.; R 3 and R 4 are the same orndifferent and each represents hydrogen, lower alkyl, etc.; nnrepresents 0 or 1; X represents -(CH 2 ) 2 -, etc.; andnY represents the formula (II);n n(wherein W represents CH or a nitrogen atom; Z 1 and Z 2 are thensame or different and each represents hydrogen, substitutednor unsubstituted lower alkyl, etc.; and Z 3 represents hydrogen,nsubstituted or unsubstituted lower alkyl, etc.)] |