Ca²⁺ signaling in myenteric interstitial cells of Cajal (ICC-MY) and their role as conditional pacemakers in the colon

Interstitial cells of Cajal in the plane of the myenteric plexus (ICC-MY) serve as electrical pacemakers in the stomach and small intestine. A similar population of cells is found in the colon, but these cells do not appear to generate regular slow wave potentials, as characteristic in more proximal gut regions. Ca2+ handling mechanisms in ICC-MY of the mouse proximal colon were studied using confocal imaging of muscles from animals expressing GCaMP6f exclusively in ICC. ICC-MY displayed stochastic, localized Ca2+ transients that seldom propagated between cells. Colonic ICC express ANO1 channels, so Ca2+ transients likely couple to activation of spontaneous transient inward currents (STICs) in these cells. The Ca2+ transients were due to Ca2+ release and blocked by cyclopiazonic acid (CPA), thapsigargin and caffeine, but unaffected by tetracaine. Antagonists of L- and T-type Ca2+ channels and reduction in extracellular Ca2+ had minimal effects on Ca2+ transients. We reasoned that STICs...,
 
Ca2+ imaging

Segments of proximal colon (1–2 cm or 2–3 cm in length) were removed from mice and placed in Krebs-Ringer bicarbonate solution (KRB). The colonic segments were opened along the mesenteric border and intraluminal contents were washed away with KRB. After removing the mucosa, the muscle sheets were pinned to a Sylgard coated dish and perfused with oxygenated KRB solution at 37 °C for a 60 min equilibration period peristaltic pump (minipuls 3, Gilson, WI, USA) with an electric in-line heater and controller (SH-27B and TC-344C, Warner instruments, CT, USA). Ca2+ imaging was performed using a spinning-disk, confocal system (CSU-W1; spinning disk, Yokogawa Electric, Tokyo, Japan) mounted on an upright Nikon Eclipse FN1 microscope equipped with several water immersion Nikon CFI Fluor lenses (10 × 0.3 NA, 20 × 0.5 NA, 40 × 0.8 NA, 60 × 0.8 NA and 100 × 1.1 NA) (Nikon Instruments, New York, USA). The system is equipped with two solid-state laser lines of 488 nm and 561 nm. The l..., , # Data from: Ca²⁺ signaling in myenteric interstitial cells of Cajal (ICC-MY) and their role as conditional pacemakers in the colon author links open overlay panel

[https://doi.org/10.5061/dryad.fttdz093m](https://doi.org/10.5061/dryad.fttdz093m)

## Description of the data and file structure

-These data files are generated using prisim software. It contains the calcium firing parameters (Frequency, duration, spatial spread and area events).

### Files and variables

#### File: ICC-MY-ALLCONTROLS-NOFLASHES-COLON-CALCIUM-.pzfx

**Description:** Dataset for stochastic calcium signals 

#### File: ICC-MY-ALLCONTROLS-FLASHES-COLON-CALCIUM-.pzfx

**Description:**  Dataset for rhythmic calcium signals 

## **-STMmaps datasets:  generated from cellular calcium transients** 

-STMmaps datasets:  generated from cellular calcium transients 

File: Paper1-Dryad.zip

The file includes datasets from ICC-MY cellular calcium events under control and pharmacological agents

This directory contains su...