BLADDER FUNCTIONAL RECOVERY FOLLOWING ACUTE OVERDISTENSION

The effects of acute overstretching on detrusor function are unclear. Based on a new method to catheterize male rat bladder through the whole urethra, three groups (control, sham-operated, and acute bladder overdistension) of male rats were utilized in the present experiment. The contraction generated by in vitro bladders immediately post-overdistension in response to 2 Hz and 32 Hz stimulation significantly decreased at 0.75 ml and 1.5 ml intravesical volumes respectively; however, by 1 day post-overdistension the contractile responses increased toward normal. By three days the ability of the bladder to generate pressure completely returned to normal, and the average bladder weight for this group was increased. Similarly, the ability to empty was reduced at 0.75 ml and 1.5 ml immediately following overdistension and recovered fully after 3 days. The ability of the sham-operated bladders to empty at high intravesical volume was slightly reduced immediately following overdistension, and this was the only pathophysiological change observed in this group. Acute bladder overdistension did not alter intravesical capacity. It is clear that acute overdistension induced reversible changes in basic bladder function.