Comparative Study of Meloxicam and Indomethacin on Ovine Ureteral Motility

Objective: To test the potentially toxic urinary tract effects of indomethacin in comparison with a novel COX-2 inhibitor, meloxicam. Method: In vitro experiments were performed using isolated ring segments of sheep ureter mounted in organ-baths. Changes in isometric tension and frequency of rhythmic contractions were assessed in control and lipopolysaccharide (LPS)-treated preparations prior to and after administration of the tested drugs. Results: Sheep ureteral rings displayed reproducible spontaneous rhythmic contractions which were abolished by indomethacin (10–6 M) and not by meloxicam (10–6 M) under control conditions. However, in LPS-treated preparations, to induce COX-2, meloxicam produced a slight inhibitory action. Conclusion: Indomethacin blocks normal motility through inhibition of COX-1, while meloxicam does not interfere with ureteral peristalsis. Meloxicam only exerts a slight inhibition in inflammation-induced preparations due to the specific action as an inhibitor of COX-2. Further studies are needed to evaluate and compare the effects of meloxicam and indomethacin from other measures of effects of COX-1 and COX-2.