ESTABLISHMENT OF AN ACUTE UTERINE CERVICAL DISTENSION MODEL IN RATS

Objective:To establish an acute uterine cervical distension (UCD) model in the lightly anesthetized rats. Methods: Ten adult female Sprague-Dawley rats were anesthetized with intraperitoneal chloralhydrate. The right carotid artery was catheterized for continuous monitoring of arterial blood pressure and heart rate. Through a small midline laparotomy, two fine metal crooks were inserted in both uterine cervical osses. With one side being fixed, UCD was performed by hanging various standard weights on another side (25, 50, 75 and 100 g). Each stimulus persisted for 10 s with 10 minute rest interval. The percentage of the area under the curve (AUC) of electromyography (EMG) in the rectus abdominis muscle between intra- and pre-stimulus was calculated as the visceromotor response (VMR) to UCD stimulus. Results: The percent changes of EMG activities induced by UCD stimuli were 25g: (182±52) %, 50g: (249±58) %, 75g: (462±113)%, and 100g: (486±110) %, respectively. All revealed significant increases compared with basal value (100%±15%) (P0.05). UCD did not induce any changes in blood pressure and heart rate. Conclusions: The present acute UCD animol model is simple and feasible, and can induce a significant and stable VMR.