Figure 4.

Ca²⁺ transients in ICC‐DMP are inhibited by nitrergic neural input. (A, B) Spatio‐temporal maps depicting Ca²⁺ transients in an ICC‐DMP in the mouse small intestine. Note the transient and spatially restricted nature of these events that are expected to couple to activation of CaCC channels in the plasma membrane. EFS (10 Hz, 0.5 ms pulse duration; 5 s; white dotted box) in panel (A) inhibited Ca²⁺ transients during the initial phase of stimulation (~2 s), and then excitatory input caused restoration of Ca²⁺ release. A rebound period of excitation occurred after cessation of EFS. (B) Addition of L‐NNA (100 μM) blocked the inhibition of Ca²⁺ transients during EFS. (C) Tabulation of effects of EFS on Ca²⁺ transient frequency (i), amplitude (ii), duration (iii), and spatial spread (iv) in ICC‐DMP during control conditions (pre‐EFS) and during the initial 2 s of EFS before and after L‐NNA (n = 5 animals; 15 cells). ns = P > 0.05; *P < 0.05; ****P < 0.0001. Copied with permission from Baker et al. (2018).