|
KMID : 0578320090270050525
|
|
Molecules and Cells
2009 Volume.27 No. 5 p.525 ~ p.531
|
|
|
Carbachol regulates pacemaker activities in cultured interstitial cells of Cajal from the mouse small intestine
|
|
So Keum-Young
Kim Sang-Hun
Sohn Hong-Moon
Choi Soo-Jin
Parajuli Shankar Prasad
Choi Seok
Yeum Cheol-Ho
Yoon Pyung-Jin
Jun Jae-Yeoul
|
|
|
Abstract
|
|
|
|
We studied the effect of carbachol on pacemaker currents in cultured interstitial cells of Cajal (ICC) from the mouse small intestine by muscarinic stimulation using a whole cell patch clamp technique and Ca2+-imaging. ICC generated periodic pacemaker potentials in the current-clamp mode and generated spontaneous inward pacemaker currents at a holding potential of?70 mV. Exposure to carbachol depolarized the membrane and produced tonic inward pacemaker currents with a decrease in the frequency and amplitude of the pacemaker currents. The effects of carbachol were blocked by 1-dimethyl-4-diphenylacetoxypiperidinium, a muscarinic M3 receptor antagonist, but not by methotramine, a muscarinic M2 receptor antagonist. Intracellular GDP-β-S suppressed the carbachol-induced effects. Carbachol-induced effects were blocked by external Na+-free solution and by flufenamic acid, a non-selective cation channel blocker, and in the presence of thapsigargin, a Ca2+-ATPase inhibitor in the endoplasmic reticulum. However, carbachol still produced tonic inward pacemaker currents with the removal of external Ca2+. In recording of intracellular Ca2+ concentrations using fluo 3-AM dye, carbachol increased intracellular Ca2+ concentrations with increasing of Ca2+ oscillations. These results suggest that carbachol modulates the pacemaker activity of ICC through the activation of non-selective cation channels via muscarinic M3 receptors by a G-protein dependent intracellular Ca2+ release mechanism.
|
|
|
KEYWORD
|
|
|
carbachol, interstitial cells of Cajal, intestine, muscarinic receptor
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
  
|