Molecular response of the bladder to obstruction.

Abstract

The unique physical attributes of the bladder wall result from the combinatorial properties of both the active, or energy dependent, and passive, or energy independent, elements. The active properties of bladder compliance are largely derived from the contributions of the detrusor smooth muscle cells, which are based upon the ATP-dependent interactions of myosin and actin. These interactions are responsible for the basal tone of the bladder wall and for its ability to fully empty. The passive properties are those that result from the structural proteins in the bladder wall. These structural proteins are involved in the transfer of tension among the cellular and extracellular matrix components, allowing for expansion of the bladder with increasing volume, but with a concurrent lack of increase in bladder pressure. The integration of both the active and passive elements determines the normal functional compliance of the bladder. Any alteration in either one of these elements can lead to abnormal bladder function.