抄録
Recent study demonstrated PGE2 receptors in various sites of micturition reflex. The purpose of this study was determination of the role of PGE2 on micturition reflex in conscious rats. Methods: Continuous measurements of micturition were performed in SD male rats (300-450g) using the metabolic cage. Number of micturition (N) and urine volume (V) was calculated. 0.5ml or 4 ml the loxprofen solution (Lox) or distilled water (DW, for control) was given orally. Results: In control (0.5ml P.O.) averaged N in first 4 hours was 3.4 and V was 2.1g. At the same time of following day, Lox (1mg/kg, 0.5ml P.O.) was given. Average N in first 4 hours was 2.6 (75%, P<0.01), and V was 1.4g (63.1%, P<0.01). Averaged N and V of after Lox administration in 24 hours did not change from the control (P=0.77 and P=0.56, respectably). V increased from the control at 8-20 hours after the drug administration. For producing the extra-urination, 4ml of water drinking was performed. In control N in first 4 hours was 4.5 and V was 4.2g after 4ml-distilled water drinking. Lox (1mg/kg, 4 ml P.O.) reduced N in 4 hours to 2.8 (61.1%, P<0.02) and V to 2.6g (61.2%, P<0.01). Averaged N and V in 24 hours did not change from the control (P=0.83 and P=0.98, respectably). Conclusion: Loxonin reduced number of micturition and voiding volume in first 4 hours. PGE2 might be important for the micturition reflex. [Jpn J Physiol 54 Suppl:S195 (2004)]
