Involvement of MAPKs and PLC Pathways in Modulation of Pacemaking Activity by So-Cheong-Ryong-Tang in Interstitial Cells of Cajal from Murine Small Intestine

Purpose. Interstitial cells of Cajal (ICCs) are the pacemaker cells that generate slow waves in the gastrointestinal (GI) tract. We have aimed to investigate the effects of Socheongryong-Tang (SCRT) in ICCs from mouse’s small intestine.Methods. The whole-cell patch-clamp configuration was used to record membrane potentials from cultured ICCs. Intracellular Ca2+([Ca2+]i) increase was studied in cultured ICCs using fura-2 AM.Results. ICCs generated pacemaker potentials in mouse’s small intestine. SCRT produced membrane depolarization in current clamp mode. Y25130 (5-HT3receptor antagonist) and RS39604 (5-HT4receptor antagonist) blocked SCRT-induced membrane depolarizations, whereas SB269970 (5-HT7receptor antagonist) did not. When GDP-β-S (1 mM) was in the pipette solution, SCRT did not induce the membrane depolarizations.[Ca2+]ianalysis showed that SCRT increased[Ca2+]i. In the presence of PD98059 (p42/44 MAPK inhibitor), SCRT did not produce membrane depolarizations. In addition, SB203580 (p38 MAPK inhibitor) and JNK inhibitors blocked the depolarizations by SCRT in pacemaker potentials. Furthermore, the membrane depolarizations by SCRT were not inhibited by U-73122, an active phospholipase C (PLC) inhibitor, but by U-73343, an inactive PLC inhibitor.Conclusion. These results suggest that SCRT might affect GI motility by the modulation of pacemaker activity through MAPKs and PLC pathways in the ICCs.

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The traditional herbal medicine, Ge-Gen-Tang, inhibits pacemaker potentials by nitric oxide/cGMP dependent ATP-sensitive K+ channels in cultured interstitial cells of Cajal from mouse small intestine

Journal of Ethnopharmacology ◽

10.1016/j.jep.2015.05.025 ◽

2015 ◽

Vol 170 ◽

pp. 201-209 ◽

Cited By ~ 11

Author(s):

Soojin Lee ◽

Huijin Gim ◽

Ji Hwan Shim ◽

Hyun Jung Kim ◽

Jong Rok Lee ◽

...

Keyword(s):

Nitric Oxide ◽

Small Intestine ◽

Herbal Medicine ◽

Interstitial Cells Of Cajal ◽

Interstitial Cells ◽

Traditional Herbal Medicine ◽

K Channels ◽

Mouse Small Intestine ◽

Pacemaker Potentials ◽

Cells Of Cajal

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Magnolia Officinalis Bark Extract Induces Depolarization of Pacemaker Potentials Through M2 and M3 Muscarinic Receptors in Cultured Murine Small Intestine Interstitial Cells of Cajal

Cellular Physiology and Biochemistry ◽

10.1159/000484065 ◽

2017 ◽

Vol 43 (5) ◽

pp. 1790-1802 ◽

Cited By ~ 4

Author(s):

Hyun Jung Kim ◽

Taewon Han ◽

Yun Tai Kim ◽

Insuk So ◽

Byung Joo Kim

Keyword(s):

Receptor Antagonist ◽

Interstitial Cells Of Cajal ◽

Interstitial Cells ◽

Pacemaker Potential ◽

Pacemaker Potentials ◽

Magnolia Officinalis ◽

Cells Of Cajal ◽

Gi Motility

Background: Magnolia officinalis Rehder and EH Wilson (M. officinalis) are traditional Chinese medicines widely used for gastrointestinal (GI) tract motility disorder in Asian countries. We investigated the effects of an ethanol extract of M. officinalis (MOE) on the pacemaker potentials of cultured interstitial cells of Cajal (ICCs) in vitro and its effects on GI motor functions in vivo. Methods: We isolated ICCs from small intestines, and the whole-cell patch-clamp configuration was used to record the pacemaker potentials in cultured ICCs in vitro. Both gastric emptying (GE) and intestinal transit rates (ITRs) were investigated in normal and GI motility dysfunction (GMD) mice models in vivo. Results: MOE depolarized ICC pacemaker potentials dose-dependently. Pretreatment with methoctramine (a muscarinic M2 receptor antagonist) and 4-DAMP (a muscarinic M3 receptor antagonist) inhibited the effects of MOE on the pacemaker potential relative to treatment with MOE alone. In addition, MOE depolarized pacemaker potentials after pretreatment with Y25130 (a 5-HT3 receptor antagonist), GR113808 (a 5-HT4 receptor antagonist) or SB269970 (a 5-HT7 receptor antagonist). However, pretreatment with RS39604 (a 5-HT4 receptor antagonist) blocked MOE-induced pacemaker potential depolarizations. Intracellular GDPβS inhibited MOE-induced pacemaker potential depolarization, as did pretreatment with Ca2+ free solution or thapsigargin. In normal mice, the GE and ITR values were significantly and dose-dependently increased by MOE. In loperamide-and cisplatin-induced GE delay models, MOE administration reversed the GE deficits. The ITRs of the GMD mice were significantly reduced relative to those of normal mice, which were significantly and dose-dependently reversed by MOE. Conclusion: These results suggest that MOE dose-dependently depolarizes ICCs pacemaker potentials through M2 and M3 receptors via internal and external Ca2+ regulation through G protein pathways in vitro. Moreover, MOE increased GE and ITRs in vivo in normal and GMD mouse models. Taken together, the results of this study show that MOE have the potential for development as a gastroprokinetic agent in GI motility function.

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Effects of ATP on Pacemaker Activity of Interstitial Cells of Cajal from the Mouse Small Intestine

Chonnam Medical Journal ◽

10.4068/cmj.2018.54.1.63 ◽

2018 ◽

Vol 54 (1) ◽

pp. 63

Author(s):

Il Koo Park ◽

Jin Ho Kim ◽

Chan Guk Park ◽

Man Yoo Kim ◽

Shankar Prasad Parajuli ◽

...

Keyword(s):

Small Intestine ◽

Interstitial Cells Of Cajal ◽

Interstitial Cells ◽

Pacemaker Activity ◽

Mouse Small Intestine ◽

Cells Of Cajal

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Action potential generation in the small intestine of W mutant mice that lack interstitial cells of Cajal

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1996.271.3.g387 ◽

1996 ◽

Vol 271 (3) ◽

pp. G387-G399 ◽

Cited By ~ 21

Author(s):

J. Malysz ◽

L. Thuneberg ◽

H. B. Mikkelsen ◽

J. D. Huizinga

Keyword(s):

Small Intestine ◽

Action Potentials ◽

Interstitial Cells Of Cajal ◽

Interstitial Cells ◽

K Channel ◽

Pacemaker Activity ◽

Channel Blockade ◽

Auerbach’S Plexus ◽

Cells Of Cajal ◽

Auerbach's Plexus

The small intestine of W/Wv mice lacks both the network of interstitial cells of Cajal (ICC), associated with Auerbach's plexus, and pacemaker activity, i.e., it does not generate slow-wave-type action potentials. The W/Wv muscle preparations showed a wide variety of electrical activities, ranging from total quiescence to generation of action potentials at regular or irregular frequency with or without periods of quiescence. The action potentials consisted of a slow component with superimposed spikes, preceded by a slowly developing depolarization and followed by a transient hyperpolarization. The action potentials were completely abolished by L-type Ca2+ channel blockers. W/Wv mice responded to K+ channel blockade (0.5 mM Ba2+ or 10 mM tetraethylammonium chloride) with effects on amplitude, frequency, rate of rise, and duration of the action potentials. In quiescent tissues from W/Wv mice, K+ channel blockade evoked the typical spikelike action potentials. Electron microscopy identified few methylene blue-positive cells in the W/Wv small intestine associated with Auerbach's plexus as individual ICC. Numbers of resident macrophage-like cells (MLC) and fibroblast-like cells (FLC) were significantly changed. Neither FLC nor MLC were part of a network nor did they form specialized junctions with neighboring cells as ICC do. Hence no cell type had replaced ICC at their normal morphological position associated with Auerbach's plexus. ICC were present in W/Wv mice at the deep muscular plexus in normal organization and numbers, indicating that they are not dependent on the Kit protein and do not take part in generation of pacemaker activity.

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Molecular markers expressed in cultured and freshly isolated interstitial cells of Cajal

AJP Cell Physiology ◽

10.1152/ajpcell.2000.279.2.c529 ◽

2000 ◽

Vol 279 (2) ◽

pp. C529-C539 ◽

Cited By ~ 131

Author(s):

Anne Epperson ◽

William J. Hatton ◽

Brid Callaghan ◽

Philip Doherty ◽

Rebecca L. Walker ◽

...

Keyword(s):

Smooth Muscle ◽

Small Intestine ◽

Interstitial Cells Of Cajal ◽

Expression Profiles ◽

Interstitial Cells ◽

Gastric Fundus ◽

Soluble Form ◽

Pacemaker Activity ◽

Murine Small Intestine ◽

Cells Of Cajal

Located within the tunica muscularis of the gastrointestinal (GI) tract are networks of cells known as interstitial cells of Cajal (ICC). ICC are critical for important basic functions of GI motility such as generation and propagation of slow-wave pacemaker activity and reception of regulatory inputs from the enteric nervous system. We have developed a novel procedure to identify and isolate individual ICC from freshly dispersed cell preparations of the murine small intestine and gastric fundus and to determine differential transcriptional expression We have compared the expression profiles of pacemaker ICC isolated from the murine small intestine (IC-MY) and ICC involved in neurotransmission from the gastric fundus (IC-IM). We have also compared expression profiles between ICC and smooth muscle cells (SMC) and between freshly isolated ICC and cultured ICC. Cultured ICC express smooth muscle myosin, whereas freshly dispersed ICC do not. All cell types express muscarinic receptor types M2and M3, neurokinin receptors NK1and NK3, and inhibitory receptor VIP-1, whereas only cultured ICC and SMC express VIP-2. Both cultured and freshly dispersed IC-IM and IC-MY express the soluble form of stem cell factor, whereas SMC from the gastric fundus express only the membrane-bound form.

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Menthol Modulates Pacemaker Potentials through TRPA1 Channels in Cultured Interstitial Cells of Cajal from Murine Small Intestine

Cellular Physiology and Biochemistry ◽

10.1159/000445549 ◽

2016 ◽

Vol 38 (5) ◽

pp. 1869-1882 ◽

Cited By ~ 12

Author(s):

Hyun Jung Kim ◽

Jinhong Wie ◽

Insuk So ◽

Myeong Ho Jung ◽

Ki-Tae Ha ◽

...

Keyword(s):

Small Intestine ◽

Membrane Potential ◽

Interstitial Cells Of Cajal ◽

Rho Kinase ◽

Thromboxane A2 ◽

Interstitial Cells ◽

Dependent Manner ◽

Induced Membrane ◽

Pacemaker Potentials ◽

Cells Of Cajal

Background/Aims: ICCs are the pacemaker cells responsible for slow waves in gastrointestinal (GI) smooth muscle, and generate periodic pacemaker potentials in current-clamp mode. Methods: The effects of menthol on the pacemaker potentials of cultured interstitial cells of Cajal (ICCs) from mouse small intestine were studied using the whole cell patch clamp technique. Results: Menthol (1 - 10 μM) was found to induce membrane potential depolarization in a concentration-dependent manner. The effects of various TRP channel antagonists were examined to investigate the receptors involved. The addition of the TRPM8 antagonist, AMTB, did not block menthol-induced membrane potential depolarizations, but TRPA1 antagonists (A967079 or HC-030031) blocked the effects of menthol, as did intracellular GDPβS. Furthermore, external and internal Ca2+ levels were found to depolarize menthol-induced membrane potentials, whereas external Na+ was not. Y-27632 (a Rho kinase inhibitor), SC-560 (a selective COX 1 inhibitor), NS-398 (a selective COX 2 inhibitor), ozagrel (a thromboxane A2 synthase inhibitor) and SQ-29548 (highly selective thromboxane receptor antagonist) were used to investigate the involvements of Rho-kinase, cyclooxygenase (COX), and the thromboxane pathway in menthol-induced membrane potential depolarizations, and all inhibitors were found to block the effect of menthol. Conclusions: These results suggest that menthol-induced membrane potential depolarizations occur in a G-protein-, Ca2+-, Rho-kinase-, COX-, and thromboxane A2-dependent manner via TRPA1 receptor in cultured ICCs in murine small intestine. The study shows ICCs are targeted by menthol and that this interaction can affect intestinal motility.

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Rikkunshito Depolarizes Pacemaker Potentials of Cultured Interstitial Cells of Cajal through Ghrelin Receptors in Murine Small Intestine

Digestion ◽

10.1159/000498986 ◽

2019 ◽

Vol 101 (3) ◽

pp. 227-238 ◽

Cited By ~ 1

Author(s):

Jeong Nam Kim ◽

Joo Hyun Nam ◽

Jong Rok Lee ◽

Sang Chan Kim ◽

Young Kyu Kwon ◽

...

Keyword(s):

Small Intestine ◽

Interstitial Cells Of Cajal ◽

Interstitial Cells ◽

Pacemaker Potentials ◽

Ghrelin Receptors ◽

Murine Small Intestine ◽

Cells Of Cajal

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Pacemaker potentials generated by interstitial cells of Cajal in the murine intestine

AJP Cell Physiology ◽

10.1152/ajpcell.00361.2004 ◽

2005 ◽

Vol 288 (3) ◽

pp. C710-C720 ◽

Cited By ~ 67

Author(s):

Yoshihiko Kito ◽

Sean M. Ward ◽

Kenton M. Sanders

Keyword(s):

Interstitial Cells Of Cajal ◽

Circular Muscle ◽

Muscle Cells ◽

Interstitial Cells ◽

Slow Waves ◽

Pacemaker Activity ◽

Dependent Manner ◽

Plateau Potential ◽

Pacemaker Potentials ◽

Cells Of Cajal

Pacemaker potentials were recorded in situ from myenteric interstitial cells of Cajal (ICC-MY) in the murine small intestine. The nature of the two components of pacemaker potentials (upstroke and plateau) were investigated and compared with slow waves recorded from circular muscle cells. Pacemaker potentials and slow waves were not blocked by nifedipine (3 μM). In the presence of nifedipine, mibefradil, a voltage-dependent Ca2+ channel blocker, reduced the amplitude, frequency, and rate of rise of upstroke depolarization (d V/d tmax) of pacemaker potentials and slow waves in a dose-dependent manner (1–30 μM). Mibefradil (30 μM) changed the pattern of pacemaker potentials from rapidly rising, high-frequency events to slowly depolarizing, low-frequency events with considerable membrane noise (unitary potentials) between pacemaker potentials. Caffeine (3 mM) abolished pacemaker potentials in the presence of mibefradil. Pinacidil (10 μM), an ATP-sensitive K+ channel opener, hyperpolarized ICC-MY and increased the amplitude and d V/d tmax without affecting frequency. Pinacidil hyperpolarized smooth muscle cells and attenuated the amplitude and d V/d tmax of slow waves without affecting frequency. The effects of pinacidil were blocked by glibenclamide (10 μM). These data suggest that slow waves are electrotonic potentials driven by pacemaker potentials. The upstroke component of pacemaker potentials is due to activation of dihydropyridine-resistant Ca2+ channels, and this depolarization entrains pacemaker activity to create the plateau potential. The plateau potential may be due to summation of unitary potentials generated by individual or small groups of pacemaker units in ICC-MY. Entrainment of unitary potentials appears to depend on Ca2+ entry during upstroke depolarization.

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