The present invention provides a pyridylaminoacetic acid compound representedby thefollowing formula (1):(see formula 1)(wherein R1, R2, R3, Y and Z are as defmed in the description and claims), orapharmacologically acceptable salt thereof. The pyridylaminoacetic acidcompound hasEP2 agonistic action and is therefore useful as a therapeutic and/orprophylactic agentfor respiratory diseases such as asthma or chronic obstructive pulmonarydisease.