[Vesical urothelium and new concepts].
Vesical urothelium was long considered to simply be a protection barrier, which passively separates the urinary content from the underlying smooth muscle and the blood stream. Recent observations, though, have pointed out that vesical urothelium cells have clear active and sensory functions, in response to various physical and chemical stimuli. Among these characteristics are the expression of several neurotransmitters and receptors: Acetylcholine, Nitric Oxide, VIP, CGRP, NKA, SP and cholinergic, vanilloid, purinergic, and tachykinin receptors. Urothelium-produced neurotransmitters are likely supposed to act through a receptor stimulation of the afferent nerve fibers within the sub-urothelial spaces. Sub-urothelial myofibroblasts are considered to play a mediation role between urothelium-produced neurotransmitters and the underlying receptors. According to these observations, a pharmacologic modulation, directly affecting the urothelium, can be hypothesized.
Clinica Urologica e Andrologica, Università degli Studi di Perugia, Ospedale Santa Maria della Misericordia, Perugia, Italy. agianton@libero.it
Antonella
A
Giannantoni
Silvia
S
Proietti
Silvia
S
Giovannozzi
Massimo
M
Porena
D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D006801:Humans; D058628:Myofibroblasts / Q000502:physiology; D018377:Neurotransmitter Agents / Q000502:physiology*; D011976:Receptors, Muscarinic / Q000502:physiology; D017981:Receptors, Neurotransmitter / Q000502:physiology*; D011983:Receptors, Purinergic / Q000502:physiology; D018039:Receptors, Tachykinin / Q000502:physiology; D012677:Sensation / Q000502:physiology; D050916:TRPV Cation Channels / Q000502:physiology; D001743:Urinary Bladder / Q000294:innervation / Q000502:physiology; D014554:Urination / Q000502:physiology; D019459:Urothelium / Q000187:drug effects / Q000502:physiology*
D018377:Neurotransmitter Agents; D011976:Receptors, Muscarinic; D017981:Receptors, Neurotransmitter; D011983:Receptors, Purinergic; D018039:Receptors, Tachykinin; D050916:TRPV Cation Channels