Regulation of Intracellular Calcium by Endoplasmic Reticulum Proteins in Small Intestinal Interstitial Cells of Cajal
Journal of Neurogastroenterology and Motility
; : 128-137, 2018.
Article
in English
| WPRIM (Western Pacific)
| ID: wpr-740725
Responsible library:
WPRO
ABSTRACT
BACKGROUND/AIMS:
We investigated the role of representative endoplasmic reticulum proteins, stromal interaction molecule 1 (STIM1), and store-operated calcium entry-associated regulatory factor (SARAF) in pacemaker activity in cultured interstitial cells of Cajal (ICCs) isolated from mouse small intestine.METHODS:
The whole-cell patch clamp technique applied for intracellular calcium ions ([Ca²+]i) analysis with STIM1 or SARAF overexpressed cultured ICCs from mouse small intestine.RESULTS:
In the current-clamping mode, cultured ICCs displayed spontaneous pacemaker potentials. External carbachol exposure produced tonic membrane depolarization in the current-clamp mode, which recovered within a few seconds into normal pacemaker potentials. In STIM1-overexpressing cultured ICCs pacemaker potential frequency was increased, and in SARAF-overexpressing ICCs pacemaker potential frequency was strongly inhibited. The application of gadolinium (a non-selective cation channel inhibitor) or a Ca2+-free solution to understand Orai channel involvement abolished the generation of pacemaker potentials. When recording intracellular Ca²+ concentration with Fluo 3-AM, STIM1-overexpressing ICCs showed an increased number of spontaneous intracellular Ca²+ oscillations. However, SARAF-overexpressing ICCs showed fewer spontaneous intracellular Ca2+ oscillations.CONCLUSION:
Endoplasmic reticulum proteins modulated the frequency of pacemaker activity in ICCs, and levels of STIM1 and SARAF may determine slow wave patterns in the gastrointestinal tract.
Full text:
Available
Database:
WPRIM (Western Pacific)
Main subject:
Carbachol
/
Calcium
/
Gastrointestinal Tract
/
Endoplasmic Reticulum
/
Interstitial Cells of Cajal
/
Gadolinium
/
Gastrointestinal Motility
/
Intestine, Small
/
Ions
/
Membranes
Limits:
Animals
Language:
English
Journal:
Journal of Neurogastroenterology and Motility
Year:
2018
Document type:
Article