PTGS2 and Ureteral obstruction: Cyclooxygenase 2 (COX-2) is induced in response to unilateral ureteral obstruction (UUO), and COX-2-derived prostaglandins have been associated with the proinflammatory response, primarily prostaglandin E2 (PGE2) and PGI2, which are increased in the early phase of inflammation [2].