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Echeverría F, Gonzalez-Sanabria N, Alvarado-Sanchez R, Fernández M, Castillo K, Latorre R. Large conductance voltage-and calcium-activated K + (BK) channel in health and disease. Front Pharmacol 2024; 15:1373507. [PMID: 38584598 PMCID: PMC10995336 DOI: 10.3389/fphar.2024.1373507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 03/12/2024] [Indexed: 04/09/2024] Open
Abstract
Large Conductance Voltage- and Calcium-activated K+ (BK) channels are transmembrane pore-forming proteins that regulate cell excitability and are also expressed in non-excitable cells. They play a role in regulating vascular tone, neuronal excitability, neurotransmitter release, and muscle contraction. Dysfunction of the BK channel can lead to arterial hypertension, hearing disorders, epilepsy, and ataxia. Here, we provide an overview of BK channel functioning and the implications of its abnormal functioning in various diseases. Understanding the function of BK channels is crucial for comprehending the mechanisms involved in regulating vital physiological processes, both in normal and pathological conditions, controlled by BK. This understanding may lead to the development of therapeutic interventions to address BK channelopathies.
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Affiliation(s)
- Felipe Echeverría
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Naileth Gonzalez-Sanabria
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Rosangelina Alvarado-Sanchez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Miguel Fernández
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Karen Castillo
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
- Centro de Investigación de Estudios Avanzados del Maule, Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, Talca, Chile
| | - Ramon Latorre
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
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Shen X, Zhang L, Jiang L, Xiong W, Tang Y, Lin L, Yu T. Alteration of sphingosine-1-phosphate with aging induces contractile dysfunction of colonic smooth muscle cells via Ca 2+ -activated K + channel (BK Ca ) upregulation. Neurogastroenterol Motil 2021; 33:e14052. [PMID: 33452855 DOI: 10.1111/nmo.14052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/13/2020] [Accepted: 11/13/2020] [Indexed: 02/04/2023]
Abstract
BACKGROUND Age-associated changes alter calcium-activated potassium channel (BKCa ) expression of colon. Sphingolipids (SLs) are important cell membrane structural components; altered composition of SLs may affect BKCa expression. This study investigated the mechanism by which sphingosine-1-phosphate (S1P) contributes to age-associated contractile dysfunction. METHODS Fifty male Sprague Dawley rats of different ages were randomly assigned to five age-groups, namely 3, 6, 12, 18, and 24 months. BKCa expression, S1P levels, and phosphorylated myosin light chain (p-MLC) levels were tested in colonic tissues. In the absence and presence of S1P treatment, BKCa expression, p-MLC levels, and intracellular calcium mobilization were tested in vitro. BKCa small interfering RNA (siRNA) was used to investigate whether p-MLC expression and calcium mobilization were affected by BKCa in colonic smooth muscle cells (SMCs). The expressions of phosphorylated protein kinase B, c-Jun N-terminal kinases (JNKs), extracellular-regulated protein kinases, nuclear factor kappa-B (NF-κB), and protein kinase Cζ (PKCζ ) were examined to investigate the correlation between S1P and BKCa . KEY RESULTS Sphingosine-1-phosphate levels and sphingosine-1-phosphate receptor 2 (S1PR2) and BKCa expressions were upregulated and p-MLC expression was downregulated in the colonic tissues, age dependently. In the cultured SMCs, S1P treatment increased BKCa expression and reduced calcium concentration and p-MLC was observed. BKCa siRNA increased calcium concentration, and p-MLC levels significantly compared with control. We also showed that S1P upregulated BKCa through PKCζ , JNK, and NF-κB pathways. CONCLUSIONS AND INFERENCES In conclusion, S1P and S1PR2 participate in age-associated contractile dysfunction via BKCa upregulation through PKCζ , JNK, and NF-κB pathways.
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Affiliation(s)
- Xiaoxue Shen
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ling Zhang
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ling Jiang
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Wenjie Xiong
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yurong Tang
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Lin Lin
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Ting Yu
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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Choi S, Kim JA, Kim TH, Li H, Shin K, Lee Y, Oh S, Pewzner‐Jung Y, Futerman AH, Suh SH. Altering sphingolipid composition with aging induces contractile dysfunction of gastric smooth muscle via K(Ca) 1.1 upregulation. Aging Cell 2015; 14:982-94. [PMID: 26288989 PMCID: PMC4693452 DOI: 10.1111/acel.12388] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/19/2015] [Indexed: 01/16/2023] Open
Abstract
KCa1.1 regulates smooth muscle contractility by modulating membrane potential, and age‐associated changes in KCa1.1 expression may contribute to the development of motility disorders of the gastrointestinal tract. Sphingolipids (SLs) are important structural components of cellular membranes whose altered composition may affect KCa1.1 expression. Thus, in this study, we examined whether altered SL composition due to aging may affect the contractility of gastric smooth muscle (GSM). We studied changes in ceramide synthases (CerS) and SL levels in the GSM of mice of varying ages and compared them with those in young CerS2‐null mice. The levels of C16‐ and C18‐ceramides, sphinganine, sphingosine, and sphingosine 1‐phosphate were increased, and levels of C22, C24:1 and C24 ceramides were decreased in the GSM of both aged wild‐type and young CerS2‐null mice. The altered SL composition upregulated KCa1.1 and increased KCa1.1 currents, while no change was observed in KCa1.1 channel activity. The upregulation of KCa1.1 impaired intracellular Ca2+ mobilization and decreased phosphorylated myosin light chain levels, causing GSM contractile dysfunction. Additionally, phosphoinositide 3‐kinase, protein kinase Cζ, c‐Jun N‐terminal kinases, and nuclear factor kappa‐B were found to be involved in KCa1.1 upregulation. Our findings suggest that age‐associated changes in SL composition or CerS2 ablation upregulate KCa1.1 via the phosphoinositide 3‐kinase/protein kinase Cζ/c‐Jun N‐terminal kinases/nuclear factor kappa‐B‐mediated pathway and impair Ca2+ mobilization, which thereby induces the contractile dysfunction of GSM. CerS2‐null mice exhibited similar effects to aged wild‐type mice; therefore, CerS2‐null mouse models may be utilized for investigating the pathogenesis of aging‐associated motility disorders.
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Affiliation(s)
- Shinkyu Choi
- Department of Physiology Medical School Ewha Womans University Seoul Korea
| | - Ji Aee Kim
- Department of Physiology Medical School Ewha Womans University Seoul Korea
| | - Tae Hun Kim
- Department of Internal Medicine Medical School Ewha Womans University Seoul Korea
| | - Hai‐yan Li
- Department of Physiology Medical School Ewha Womans University Seoul Korea
| | - Kyong‐Oh Shin
- College of Pharmacy and MRC Chungbuk National University Chongju Korea
| | - Yong‐Moon Lee
- College of Pharmacy and MRC Chungbuk National University Chongju Korea
| | - Seikwan Oh
- Department of Molecular Medicine Medical School Ewha Womans University Seoul Korea
| | - Yael Pewzner‐Jung
- Department of Biological Chemistry Weizmann Institute of Science Rehovot Israel
| | - Anthony H. Futerman
- Department of Biological Chemistry Weizmann Institute of Science Rehovot Israel
| | - Suk Hyo Suh
- Department of Physiology Medical School Ewha Womans University Seoul Korea
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Venglovecz V, Rakonczay Z, Gray MA, Hegyi P. Potassium channels in pancreatic duct epithelial cells: their role, function and pathophysiological relevance. Pflugers Arch 2014; 467:625-40. [PMID: 25074489 DOI: 10.1007/s00424-014-1585-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/09/2014] [Accepted: 07/18/2014] [Indexed: 12/14/2022]
Abstract
Pancreatic ductal epithelial cells play a fundamental role in HCO3 (-) secretion, a process which is essential for maintaining the integrity of the pancreas. Although several studies have implicated impaired HCO3 (-) and fluid secretion as a triggering factor in the development of pancreatitis, the mechanism and regulation of HCO3 (-) secretion is still not completely understood. To date, most studies on the ion transporters that orchestrate ductal HCO3 (-) secretion have focussed on the role of Cl(-)/HCO3 (-) exchangers and Cl(-) channels, whereas much less is known about the role of K(+) channels. However, there is growing evidence that many types of K(+) channels are present in ductal cells where they have an essential role in establishing and maintaining the electrochemical driving force for anion secretion. For this reason, strategies that increase K(+) channel function may help to restore impaired HCO3 (-) and fluid secretion, such as in pancreatitis, and therefore provide novel directions for future pancreatic therapy. In this review, our aims are to summarize the types of K(+) channels found in pancreatic ductal cells and to discuss their individual roles in ductal HCO3 (-) secretion. We will also describe how K(+) channels are involved in pathophysiological conditions and discuss how they could act as new molecular targets for the development of therapeutic approaches to treat pancreatic diseases.
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Affiliation(s)
- Viktória Venglovecz
- Department of Pharmacology and Pharmacotherapy, University of Szeged, Szeged, Hungary,
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Hayashi M, Novak I. Molecular basis of potassium channels in pancreatic duct epithelial cells. Channels (Austin) 2013; 7:432-41. [PMID: 23962792 PMCID: PMC4042478 DOI: 10.4161/chan.26100] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Potassium channels regulate excitability, epithelial ion transport, proliferation, and apoptosis. In pancreatic ducts, K+ channels hyperpolarize the membrane potential and provide the driving force for anion secretion. This review focuses on the molecular candidates of functional K+ channels in pancreatic duct cells, including KCNN4 (KCa3.1), KCNMA1 (KCa1.1), KCNQ1 (Kv7.1), KCNH2 (Kv11.1), KCNH5 (Kv10.2), KCNT1 (KCa4.1), KCNT2 (KCa4.2), and KCNK5 (K2P5.1). We will give an overview of K+ channels with respect to their electrophysiological and pharmacological characteristics and regulation, which we know from other cell types, preferably in epithelia, and, where known, their identification and functions in pancreatic ducts and in adenocarcinoma cells. We conclude by pointing out some outstanding questions and future directions in pancreatic K+ channel research with respect to the physiology of secretion and pancreatic pathologies, including pancreatitis, cystic fibrosis, and cancer, in which the dysregulation or altered expression of K+ channels may be of importance.
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Affiliation(s)
- Mikio Hayashi
- Department of Biology; University of Copenhagen; Copenhagen, Denmark
| | - Ivana Novak
- Department of Biology; University of Copenhagen; Copenhagen, Denmark
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Kazama I, Maruyama Y, Murata Y, Sano M. Voltage-dependent biphasic effects of chloroquine on delayed rectifier K(+)-channel currents in murine thymocytes. J Physiol Sci 2012; 62:267-74. [PMID: 22328488 PMCID: PMC10716932 DOI: 10.1007/s12576-012-0195-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 01/20/2012] [Indexed: 11/29/2022]
Abstract
Lymphocytes are of rich in delayed rectifier K(+)-channels (Kv1.3) in their plasma membranes, and the channels play crucial roles in the lymphocyte activation and proliferation. Since chloroquine, a widely used anti-malarial drug, exerts immunosuppressive effects, it will affect the channel currents in lymphocytes. In the present study, employing the standard patch-clamp whole-cell recording technique, we examined the effects of chloroquine on the channels expressed in murine thymocytes. Published papers report that chloroquine will inhibit voltage-dependent K(+)-channel currents by plugging into the open-pore. We observed, indeed, that chloroquine suppressed the pulse-end currents of Kv1.3-channels at higher voltage steps. Surprisingly, however, we found that the drug enhanced the peak currents at both higher and lower voltage steps. Since chloroquine showed such biphasic effects on the thymocyte K(+)-channels, and since those effects were voltage dependent, we examined the effects of chloroquine on the activation and the inactivation of the channel currents. We noted that chloroquine shifted both the activation and the inactivation curves toward the hyperpolarizing potential, and that those shifts were more emphasized at lower voltage steps. We conclude that chloroquine facilitates both the activation and the inactivation of Kv1.3-channel currents in thymocytes, and that those effects are voltage dependent.
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Affiliation(s)
- I Kazama
- Department of Physiology I, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Miyagi, Japan.
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Kazama I, Maruyama Y, Murata Y. Suppressive effects of nonsteroidal anti-inflammatory drugs diclofenac sodium, salicylate and indomethacin on delayed rectifier K+-channel currents in murine thymocytes. Immunopharmacol Immunotoxicol 2012; 34:874-8. [PMID: 22409730 DOI: 10.3109/08923973.2012.666249] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Lymphocytes predominantly express delayed rectifier K(+)-channels (Kv1.3) in their plasma membranes, and the channels play crucial roles in the lymphocyte activation and proliferation. Since nonsteroidal anti-inflammatory drugs (NSAIDs), the most commonly used analgesic and antipyretic drugs, exert immunomodulatory effects, they would affect the channel currents in lymphocytes. In the present study, employing the standard patch-clamp whole-cell recording technique, we examined the effects of diclofenac sodium, salicylate and indomethacin on the channel currents in murine thymocytes and the membrane capacitance. Diclofenac sodium and salicylate significantly suppressed the pulse-end currents of the channel. However, indomethacin suppressed both the peak and the pulse-end currents with a significant increase in the membrane capacitance. This study demonstrated for the first time that NSAIDs, such as diclofenac sodium, salicylate and indomethacin, exert inhibitory effects on thymocyte Kv1.3-channel currents. The slow inactivation pattern induced by indomethacin was thought to be associated with microscopic changes in the plasma membrane surface detected by the increase in the membrane capacitance.
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Affiliation(s)
- Itsuro Kazama
- Department of Physiology I, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Miyagi, Japan.
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Heitzmann D, Warth R. Physiology and pathophysiology of potassium channels in gastrointestinal epithelia. Physiol Rev 2008; 88:1119-82. [PMID: 18626068 DOI: 10.1152/physrev.00020.2007] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Epithelial cells of the gastrointestinal tract are an important barrier between the "milieu interne" and the luminal content of the gut. They perform transport of nutrients, salts, and water, which is essential for the maintenance of body homeostasis. In these epithelia, a variety of K(+) channels are expressed, allowing adaptation to different needs. This review provides an overview of the current literature that has led to a better understanding of the multifaceted function of gastrointestinal K(+) channels, thereby shedding light on pathophysiological implications of impaired channel function. For instance, in gastric mucosa, K(+) channel function is a prerequisite for acid secretion of parietal cells. In epithelial cells of small intestine, K(+) channels provide the driving force for electrogenic transport processes across the plasma membrane, and they are involved in cell volume regulation. Fine tuning of salt and water transport and of K(+) homeostasis occurs in colonic epithelia cells, where K(+) channels are involved in secretory and reabsorptive processes. Furthermore, there is growing evidence for changes in epithelial K(+) channel expression during cell proliferation, differentiation, apoptosis, and, under pathological conditions, carcinogenesis. In the future, integrative approaches using functional and postgenomic/proteomic techniques will help us to gain comprehensive insights into the role of K(+) channels of the gastrointestinal tract.
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Affiliation(s)
- Dirk Heitzmann
- Institute of Physiology and Clinic and Policlinic for Internal Medicine II, Regensburg, Germany
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Yeh J, Kim BS, Gaines L, Peresie J, Page C, Arroyo A. The expression of hyperpolarization activated cyclic nucleotide gated (HCN) channels in the rat ovary are dependent on the type of cell and the reproductive age of the animal: a laboratory investigation. Reprod Biol Endocrinol 2008; 6:35. [PMID: 18710573 PMCID: PMC2533335 DOI: 10.1186/1477-7827-6-35] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Accepted: 08/18/2008] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Aim of this study was to test the hypothesis that levels of hyperpolarization activated cyclic nucleotide gated channels 1 to 4 (HCN1-4) are linked to the reproductive age of the ovary. METHODS Young, adult, and reproductively aged ovaries were collected from Sprague-Dawley rats. RT-PCR and western blot analysis of ovaries was performed to investigate the presence of mRNA and total protein for HCN1-4. Immunohistochemistry with semiquantitative H score analysis was performed using whole ovarian histologic sections. RESULTS RT-PCR analysis showed the presence of mRNA for HCN1-4. Western blot analysis revealed HCN1-3 proteins in all ages of ovarian tissues. Immunohistochemistry with H score analysis demonstrated distinct age-related changes in patterns of HCN1-3 in the oocytes, granulosa cells, theca cells, and corpora lutea. HCN4 was present only in the oocytes, with declining levels during the reproduction lifespan. CONCLUSION The evidence presented here demonstrates cell-type and developmental age patterns of HCN1-4 channel expression in rat ovaries. Based on this, we hypothesize that HCN channels have functional significance in rat ovaries and may have changing roles in reproductive aging.
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Affiliation(s)
- John Yeh
- Department of Gynecology-Obstetrics, University at Buffalo, The State University of New York, Buffalo, New York, 14222, USA
| | - Beom Su Kim
- Department of Gynecology-Obstetrics, University at Buffalo, The State University of New York, Buffalo, New York, 14222, USA
| | - Larry Gaines
- Department of Gynecology-Obstetrics, University at Buffalo, The State University of New York, Buffalo, New York, 14222, USA
| | - Jennifer Peresie
- Department of Gynecology-Obstetrics, University at Buffalo, The State University of New York, Buffalo, New York, 14222, USA
| | - Carly Page
- Department of Gynecology-Obstetrics, University at Buffalo, The State University of New York, Buffalo, New York, 14222, USA
| | - Armando Arroyo
- Department of Gynecology-Obstetrics, University at Buffalo, The State University of New York, Buffalo, New York, 14222, USA
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Petersen OH. Ca2+ signalling and Ca2+-activated ion channels in exocrine acinar cells. Cell Calcium 2008; 38:171-200. [PMID: 16107275 DOI: 10.1016/j.ceca.2005.06.024] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2005] [Accepted: 06/28/2005] [Indexed: 01/11/2023]
Abstract
The development of the calcium signalling field, from its early beginnings some 40 years ago to the present, is described. Calcium signalling in exocrine gland acinar cells and the effects of neurotransmitter- or hormone-elicited rises in the cytosolic calcium ion concentration on ion channel gating are reviewed. The highly polarized arrangement of the organelle systems in living acinar cells is described as well as its importance for the physiologically relevant local and polarized calcium signalling events.
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Affiliation(s)
- Ole H Petersen
- MRC Group, The Physiological Laboratory, University of Liverpool, Crown Street, Liverpool L69 3BX, UK.
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Gerasimenko JV, Sherwood M, Tepikin AV, Petersen OH, Gerasimenko OV. NAADP, cADPR and IP3 all release Ca2+ from the endoplasmic reticulum and an acidic store in the secretory granule area. J Cell Sci 2006; 119:226-38. [PMID: 16410548 DOI: 10.1242/jcs.02721] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Inositol trisphosphate and cyclic ADP-ribose release Ca2+ from the endoplasmic reticulum via inositol trisphosphate and ryanodine receptors, respectively. By contrast, nicotinic acid adenine dinucleotide phosphate may activate a novel Ca2+ channel in an acid compartment. We show, in two-photon permeabilized pancreatic acinar cells, that the three messengers tested could each release Ca2+ from the endoplasmic reticulum and also from an acid store in the granular region. The nicotinic acid adenine dinucleotide phosphate action on both types of store, like that of cyclic ADP-ribose but unlike inositol trisphosphate, depended on operational ryanodine receptors, since it was blocked by ryanodine or ruthenium red. The acid Ca2+ store in the granular region did not have Golgi or lysosomal characteristics and might therefore be associated with the secretory granules. The endoplasmic reticulum is predominantly basal, but thin extensions penetrate into the granular area and cytosolic Ca2+ signals probably initiate at sites where endoplasmic reticulum elements and granules come close together.
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Affiliation(s)
- Julia V Gerasimenko
- MRC Secretory Control Research Group, The Physiological Laboratory, University of Liverpool, Crown Street, Liverpool, L69 3BX, UK.
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Wu YL, Ohsaga A, Oshiro T, Iinuma K, Kondo Y, Ebihara S, Sasaki H, Maruyama Y. Suppressive effects of red wine polyphenols on voltage-gated ion channels in dorsal root ganglionic neuronal cells. TOHOKU J EXP MED 2005; 206:141-50. [PMID: 15888970 DOI: 10.1620/tjem.206.141] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Polyphenols are ubiquitous plant metabolites with multiple pharmacological properties. Using whole-cell patch-clamp current recording techniques, we studied the effects of polypnenols extracted from red wine (purity > 90% from Cabernet Sauvignon grape wine) on the activities of voltage-operated Na+-, K+-, and Ca2+-channel currents in mouse dorsal root ganglionic neuronal cells. The polyphenols suppressed all of the channel activities with half-effective concentrations of about 2.5, 4.0, and 0.8-1.5 micro g/ml, respectively. In contrast, they showed no noticeable effects on the ion channels in other types of cells, including large conductance K+-channels in mouse lacrimal acinar cells. Thus, the polyphenols suppress firings of the action potential in the neuronal cells and could show a sedative effect on the excitation. We expect that red wine can be used as a remedy for excessive sensory stimuli.
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Affiliation(s)
- Yan L Wu
- Department of Physiology, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan
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