Fig. 7
An outline of the predictive signaling events activated by stimulation of the urothelial cells leading to the urothelial cell-mediated local bladder contractions. (1) The urothelial cell stimulation causes the release of ATP. Then the released ATP activates the purinergic signaling components on the detrusor smooth muscles. (2) The released ATP also acts as a mediator of releasing ACh from the urothelium. The released ACh then activates the muscarinic signaling events on the detrusor smooth muscles. (3) G-protein coupled receptors (GPCR) are involved in producing the urothelial cell-mediated local bladder contractions and it is related to the ACh activation of muscarinic receptors which thereafter activates the GPCR signaling to produce depolarization and contractions. (4) The urothelial cell-mediated local bladder contractions signaling eventually causes the opening of voltage dependent Ca2+ channels to influx extracellular calcium into the cells. (5) Stimulation of the urothelial cells releases ATP and ACh by means of exocytosis and hemichannels
