Bladder inflammation and hypogastric neurectomy influence uterine motility in the rat

How pathophysiology of one pelvic organ influences the physiology of another is poorly understood. Here we compared the influence of bladder inflammation and hypogastric neurectomy (HYPX) on uterine contractions and bladder reflexes in urethane-anesthetized rats. Uterine contractions were measured via a latex balloon in one uterine horn. Bladder reflexes were assessed by micturition thresholds (MT) obtained cystometrographically. Whereas bladder inflammation significantly increased bladder reflexes (i.e., reduced MTs), it significantly decreased uterine contraction rate. Whereas HYPX produced small significant decreases in MT, it decreased the rate and significantly increased the amplitude of uterine contractions. These results indicate that bladder pathophysiology can influence uterine contractions and that some of this influence may be via the hypogastric nerve. Such viscero-visceral interactions likely involve spinal cord mechanisms and may have considerable clinical relevance.