The effect of short-term obstruction on urinary bladder function in the rabbit.

The effect of short term partial obstruction on urinary bladder function was studied in rabbits. After 1 week of partial bladder obstruction, the bladders were significantly hypertrophied with a mass over 9 times that of control bladders. The obstruction resulted in a marked decrease in both intracellular ATP and muscarinic receptor density. In vitro response of isolated smooth muscle strips from the obstructed bladder body to cholinergic stimulation was only 50 per cent of the response of control bladders. The obstructed bladder was able to expel only 28 per cent of its volume whereas control bladders expelled 100 per cent of their volume. The results of these studies demonstrate the rapid nature of the response of the bladder to chronic obstruction. Within 1 week frank hypertrophy and significant defects in the contractile ability of the bladder were evident.