Micturition in Normal and Hypertensive Conscious Rat: Sex Difference in Cyclooxygenase Inhibition

Background: With reference to our recent observations that there is a sex difference in the micturition pattern be-tween male and female normotensive Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR), the aim in this investigation was to examine the respective contribution of cyclooxygenase (COX)-1 vs. COX-2 inhibition in the micturi-tion pattern of male and female SHR and WKY rats. Materials and Methods: Cystometry was performed in conscious male and female SHR and WKY rats. Void volume, void interval, and peak void pressure were measured during cystometry before and after intraduodenal administration of ketopro-fen (10 mg/kg), a relatively selective inhibitor against COX-1, and meloxicam (10 mg/kg), a selective COX-2 inhibitor. Results: Male SHR and WKY had shorter void intervals than female SHR and WKY under control conditions. Ketoprofen and meloxicam increased void interval in male WKY (124 and 59%), male SHR (119 and 127%), female WKY (33 and 30%), and female SHR (50 and 34%), compared to their respective vehicle groups. Conclusion: Present study indicates that ke-toprofen and meloxicam had a robust effect on micturition in male SHR and WKY than female SHR and WKY. The COX-