Fig. 6. Hypotheses for possible mechanisms of this study. i) Light induces an inward current in interstitial cells of Cajal (ICC) via activation of channelrhodopsin-2 (ChR2); ii) the inward current causes depolarization of ICC; iii) some ICC have voltage-dependent inward currents (Cav3.2) that might amplify the depolarization and admit Ca2+; iv) Ca2+ entry causes activation of anoctamin 1 (ANO1) channels and/or Ca2+-induced Ca2+ release (CICR); v) increased intracellular Ca2+ concentration in ICC activates ANO1 channels; vi) Cl- efflux through ANO1 channels is equivalent to the inward current and this causes further depolarization; vii) depolarizing currents are conducted to smooth muscle cells (SMCs) via gap junction coupling and activate L-type Ca2+ channels (Cav1.2); viii) Ca2+ entry in SMCs through Cav1.2 initiates contraction.
© J Neurogastroenterol Motil
