Urinary bladder disorders: Is adenosine friend or foe?

• Type: Chapter or Part of a Book
• Date: 2014

Authors

Silva Ramos, M (Author) Other; Silva, I (Author) Other; Miguel Faria (Author) ICBAS; Magalhães Cardoso, MT (Author) Other; Paulo Correia de Sá (Author) ICBAS

Book

Title: Adenosine Receptors: Pharmacology, Functions and Therapeutic Aspects

Pages: 115-141

ISBN: 9781634634717; 9781634634540

Indexing

Scopus - 1 Citation

Other information

Authenticus ID: P-00K-4C9

Abstract (EN): There is a considerable bulk of evidence for the relevance of ATP in the regulation of bladder function in health and in disease conditions. However the actions of its metabolite, adenosine, on bladder tissue only recently are being unveiled. All four subtypes of adenosine receptors (A1, A2aA2A, A2B and A3) have been identified in the bladder of experimental animals by RT-PCR and Western blot analysis; these receptors are differently distributed among the urothelium and detrusor layers. Adenosine receptors are also present in the human bladder where they can modulate filling sensations and voiding. While adenosine inhibits nerve-evoked acetylcholine release from cholinergic nerve efferents, via high affinity A1 receptors, high concentrations of the nucleoside are required to reduce detrusor contractions induced by carbachol, ATP and potassium depolarizations. Characterization of the adenosine receptor involved in detrusor smooth muscle relaxation is still a matter of debate. Besides the major effects of the nucleoside on bladder voiding, adenosine also influences the filling phase of the micturition reflex by controlling the release of ATP from urothelial cells and the firing of sensory nerve afferents, via A1 receptors activation. Differences in the kinetics of ATP metabolism by ectonucleotidases and adenosine biosynthesis between luminal and serosal sides of the urothelium may explain the dominant role of adenosine in the suburothelium and detrusor smooth muscle layers. Thus, the adenosine signaling pathway is now being explored as a potential therapeutic target for human bladder disorders, including inflammatory diseases, overactivity and outflow obstruction.

Language: English

Type (Professor's evaluation): Scientific