Hyperpolarization-activated cyclic nucleotide-gated channels working as pacemaker channels in colonic interstitial cells of Cajal.

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels function as pacemaker channels in spontaneously active cells. We studied the existence of HCN channels and their functional roles in the interstitial cells of Cajal (ICC) from the mouse colon using electrophysiological, immunohistochemical and molecular techniques. HCN1 and HCN3 channels were detected in anoctamin-1 (Ca -activated Cl channel; ANO1)-positive cells within the muscular and myenteric layers in colonic tissues.

Effects of Ca2+-Activated Cl- Channel ANO1inhibitors on Pacemaker Activity in Interstitial Cells of Cajal.

Background/aims: Anoctamin1 (Ca2+-activated Cl- channel, ANO1) is a specific marker of the interstitial cells of Cajal (ICC) in the gastrointestinal tract, and are candidate proteins that can function as pacemaker channels. Recently, novel selective ANO1 inhibitors were discovered and used to study Ca2+-activated Cl- channels. Therefore, to investigate whether ANO1 channels function as pacemaker channels, selective ANO1 inhibitors were tested with respect to the pacemaker potentials in ICC.

Regulation of Intracellular Calcium by Endoplasmic Reticulum Proteins in Small Intestinal Interstitial Cells of Cajal.

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 ([Ca]) analysis with STIM1 or SARAF overexpressed cultured ICCs from mouse small intestine.

Results: In the current-clamping mode, cultured ICCs displayed spontaneous pacemaker potentials.

Prostanoid EP3 receptor agonist sulprostone enhances pacemaker activity of colonic interstitial cells of Cajal.

EP receptor activation by PGE2 regulates gastrointestinal motility by modulating smooth muscle contractility. Interstitial cells of Cajal (ICCs) are pacemaker cells that regulate smooth muscle activity. We aimed to determine effects of the EP3 receptor agonist sulprostone on pacemaker potentials in colonic ICCs.

ATP-sensitive K channels maintain resting membrane potential in interstitial cells of Cajal from the mouse colon.

To investigate the role of ATP-sensitive K(K) channels on pacemaker activity in interstitial cells of Cajal (ICC), whole-cell patch clamping, RT-PCR, and intracellular Ca([Ca]) imaging were performed in cultured colonic ICC. Pinacidil (a K channel opener) hyperpolarized the membrane and inhibited the generation of pacemaker potential, and this effect was reversed by glibenclamide (a K channel blocker). RT-PCR showed that K 6.

Pituitary Adenylate Cyclase-activating Polypeptide Inhibits Pacemaker Activity of Colonic Interstitial Cells of Cajal.

This study aimed to investigate the effect of pituitary adenylate cyclase-activating peptide (PACAP) on the pacemaker activity of interstitial cells of Cajal (ICC) in mouse colon and to identify the underlying mechanisms of PACAP action. Spontaneous pacemaker activity of colonic ICC and the effects of PACAP were studied using electrophysiological recordings. Exogenously applied PACAP induced hyperpolarization of the cell membrane and inhibited pacemaker frequency in a dose-dependent manner (from 0.

Functional effects of β3-adrenoceptor on pacemaker activity in interstitial cells of Cajal from the mouse colon.

We investigated the presence of β3-adrenoceptor and its functional effects on pacemaker potentials in colonic interstitial cells of Cajal (ICCs) from mice. The whole-cell patch clamp technique was used to record pacemaker potentials in cultured ICCs and reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the mRNA transcript levels β-adrenoceptors. The β3-adrenoceptor agonist, BRL37344, reduced the frequency of pacemaker potentials in a concentration-dependent manner.

Not only hysterectomy but also cesarean section can predict incomplete flexible sigmoidoscopy among patients with prior abdominal or pelvic surgery.

Background: Flexible sigmoidoscopy (FS) is a safe and effective method for colorectal cancer (CRC) screening. Several studies have demonstrated that individuals who have undergone surgery are at a greater risk of having incomplete FS. This study explored predictors of incomplete FS and reduced polyp detection rates for participants who had undergone abdominal or pelvic surgery.

Spontaneous electrical activity of cultured interstitial cells of cajal from mouse urinary bladder.

Interstitial cells of Cajal (ICCs) from the urinary bladder regulate detrusor smooth muscle activities. We cultured ICCs from the urinary bladder of mice and performed patch clamp and intracellular Ca(2+) ([Ca(2+)]i) imaging to investigate whether cultured ICCs can be a valuable tool for cellular functional studies. The cultured ICCs displayed two types of spontaneous electrical activities which are similar to those recorded in intact bladder tissues.