SPC bladder drainage results in a high patient satisfaction rate. Patients and clinicians should be aware of the potential complications associated with SPC insertion.

The urothelium is a newly recognized sensory structure that detects bladder fullness. Pivotal to this sensory role is the release of ATP from the urothelium. However, the routes for urothelial ATP release, its modulation by receptor-mediated pathways, and the autocrine/paracrine role of ATP are poorly understood, especially in native tissue. We examined the action of key neurotransmitters: purinergic and muscarinic agonists on ATP release and its paracrine effect. Guinea pig and human urothelial mucosa were mounted in a perfusion trough; superfusate ATP was measured using a luciferin-luciferase assay, and tissue contractions were recorded with a tension transducer. Intracellular Ca2+ was measured in isolated urothelial cells with fura-2. The P2Y agonist UTP but not the P2X agonist α,β-methylene-ATP generated ATP release. The muscarinic agonist carbachol and the M2-preferential agonist oxotremorine also generated ATP release, which was antagonized by the M2-specific agent methoctramine. Agonist-evoked ATP release was accompanied by mucosal contractions. Urothelial ATP release was differentially mediated by intracellular Ca2+ release, cAMP, exocytosis, or connexins. Urothelium-attached smooth muscle exhibited spontaneous contractions that were augmented by subthreshold concentrations of carbachol, which had little direct effect on smooth muscle. This activity was attenuated by desensitizing P2X receptors on smooth muscle. Urothelial ATP release was increased in aging bladders. Purinergic and muscarinic agents produced similar effects in human urothelial tissue. This is the first demonstration of specific modulation of urothelial ATP release in native tissue by purinergic and muscarinic neurotransmitters via distinct mechanisms. Released ATP produces paracrine effects on underlying tissues. This process is altered during aging and has relevance to human bladder pathologies.

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What ' s known on the subject? and What does the study add? The optimal method of active surveillance in prostate cancer remains unknown. This study is one of the fi rst to report on the role of transperineal template prostate biopsies in active surveillance. It demonstrates that around one third of men are reclassifi ed with more signifi cant prostate cancer at an early stage in their management. This is a higher proportion than reported in contemporary cancers using standard transrectal biopsies for restaging.

The basic electrophysiological properties of the human detrusor have been investigated in vitro using isolated single cells obtained by collagenase digestion of bladder biopsy specimens. Recordings were made using the 'whole-cell patch clamp' technique using either a physiological filling solution or one in which cesium was used to block any outward current. Spontaneous and stimulated action potentials have been recorded and we have performed the first voltage clamp analysis of the currents that underlie the action potential in human detrusor. The depolarising phase of the action potential occurs by an inward current of Ca2+ ions which can be shown to be of sufficient magnitude to support the rate of upstroke. Repolarisation occurs due to an outward K+ current that is partially Ca2+ dependent. The techniques described here permit the investigation of the ionic basis for the control of contractility in the human bladder and may permit the characterisation of any underlying abnormality in the overactive detrusor.