In vivo paracrine effects of ATP-induced urothelial acetylcholine in the rat urinary bladder.

In vivo paracrine effects of ATP-induced urothelial acetylcholine in the rat urinary bladder. Auton Neurosci. 2020 May 23;227:102689 Authors: Stenqvist J, Aronsson P, Carlsson T, Winder M, Tobin G Abstract Mechanical stretch of the urothelium induces the release of ATP that activates bladder afferent nerves. In the rat urinary bladder, ATP is also a contractile co-transmitter in the parasympathetic innervation. In isolated preparations, ATP evokes a urothelial release of acetylcholine that substantially contributes to ATP-evoked contractile responses. Currently we aimed to further examine the interactions of ATP and acetylcholine in the rat urinary bladder in two in vivo models. In the whole bladder preparation, atropine reduced ATP-evoked responses by about 50% in intact but denervated bladders, while atropine had no effect after denudation of the urothelium. In a split bladder preparation, reflex-evoked responses of the contralateral half were studied by applying stimuli (agonists or stretch) to the ipsilateral half. Topical administration of ATP and methacholine as well as of stretch induced contralateral reflex-evoked contractions. While topical administration of atropine ipsilaterally reduced the ATP- and stretch-induced contralateral contractions by 27 and 39%, respectively, the P2X purinoceptor antagonist PPADS reduced them by 74 and 84%. In contrary, the muscarinic M2-(M4)-selective receptor antagonist methoctramine increased...
Source: Autonomic Neuroscience - Category: Neuroscience Authors: Tags: Auton Neurosci Source Type: research