Fig. 2

Optogenetic activation of urothelial cells produced local bladder contractions. (a) Representative recording of the urothelial cell-mediated local bladder contractions evoked by blue light (20 mW, 5 s) and red light (20 mW, 5 s), showed that only the blue light activates the ChR2 expressed into the urothelial cells in UPK2-ChR2 Cre⁺ mice and produces contractions. (b) Unlike the UPK2-ChR2 Cre⁺ mice, UPK2-ChR2 Cre^– mice that do not express ChR2 into the urothelial cells did not produce contractions in response to blue light (20 mW, 5 s). (c) Summarized data of the urothelial cell-mediated local bladder contractions. The amplitude of the urothelial cell-mediated local bladder contractions was expressed as a percentage of the 70 mM KCl-evoked contractions in the same preparation. Each point represents the mean ± SD of the mean (n = 5 for UPK2-ChR2 Cre⁺ mice and n = 4 for UPK2-ChR2 Cre^–mice). Blue or red bars correspond to light stimulation