Signalling molecules in the urothelium.

Michael Winder,Rok Romih,Gunnar Tobin,Daša Zupančič

doi:10.1155/2014/297295

Michael Winder, Rok Romih + Show 2 more

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https://doi.org/10.1155/2014/297295

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Abstract

The urothelium was long considered to be a silent barrier protecting the body from the toxic effects of urine. However, today a number of dynamic abilities of the urothelium are well recognized, including its ability to act as a sensor of the intravesical environment. During recent years several pathways of these urothelial abilities have been proposed and a major part of these pathways includes release of signalling molecules. It is now evident that the urothelium represents only one part of the sensory web. Urinary bladder signalling is finely tuned machinery of signalling molecules, acting in autocrine and paracrine manner, and their receptors are specifically distributed among different types of cells in the urinary bladder. In the present review the current knowledge of the formation, release, and signalling effects of urothelial acetylcholine, ATP, adenosine, and nitric oxide in health and disease is discussed.

Highlights

The urothelium is a stratified epithelium that covers the inner parts of the renal pelvis, ureters, and urinary bladder and parts of the urethra
The acetylcholine effect on afferent muscarinic receptors seems to be one important target for drugs used to treat the overactive bladder [14, 15]. These effects, together with the number of signalling molecules produced by the urothelium, in particular ATP, adenosine, and nitric oxide, implicate the involvement of the urothelium in various mechanisms involved in lower urinary
Studies in the mouse urinary bladder have shown a cellspecific expression pattern of ectonucleotidases within the urothelium, lamina propria, blood vessels, and smooth muscle cells and they likely act in a coordinated manner to regulate adenosine availability to purinergic receptors [95]

Summary

Introduction

The urothelium is a stratified epithelium that covers the inner parts of the renal pelvis, ureters, and urinary bladder and parts of the urethra. The urothelium can interact with underlying tissues by release of additional signalling molecules upon activation of urothelial cell surface receptors (Table 1). Another important implication of the urothelial function is its role in lower urinary tract disorders. The acetylcholine effect on afferent muscarinic receptors seems to be one important target for drugs used to treat the overactive bladder [14, 15] These effects, together with the number of signalling molecules produced by the urothelium, in particular ATP, adenosine, and nitric oxide, implicate the involvement of the urothelium in various mechanisms involved in lower urinary. The current knowledge of the functional roles of key urothelial signalling molecules, such as acetylcholine, ATP, adenosine, and nitric oxide, is reviewed

Acetylcholine

Method of detection

ACh ACh

Adenosine

Nitric Oxide

Conclusion