Prostanoids as local modulators of reflex micturition.

Surge of interest about the possible role of prostanoids in the regulation of urinary bladder function can be traced back to the early 1970s, after the demonstration that prostaglandin-like material is released in the circulation during or immediately after bladder distension. The discovery that even a mild form of tissue stimulation, such as stretch of smooth muscle cells, releases significant amounts of prostanoids prompted the speculation that locally generated prostaglandins (PGs) might aid the receptive functions of hollow organs, such as the stomach and the urinary bladder, thereby allowing accommodation of their physiological content. While the latter interpretation turned out to be incorrect for the urinary bladder, these earlier studies attracted the attention of many investigators on the possible role of prostanoids as local modulators of micturition. This topic has been the subject of some recent reviews addressing the effect of prostanoids in regulating motility, blood flow, defence against infection and carcinogenesis in the urinary bladder. The aim of this short review is to re-address the topic of prostanoid modulation of reflex micturition with particular emphasis on a target for prostanoid action in the urinary bladder (i.e. sensory nerves) which, until recently, has been somehow neglected.