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Diszházi G, Magyar ZÉ, Lisztes E, Tóth-Molnár E, Nánási PP, Vennekens R, Tóth BI, Almássy J. TRPM4 links calcium signaling to membrane potential in pancreatic acinar cells. J Biol Chem 2021; 297:101015. [PMID: 34329682 PMCID: PMC8371206 DOI: 10.1016/j.jbc.2021.101015] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 01/02/2023] Open
Abstract
Transient receptor potential cation channel subfamily M member 4 (TRPM4) is a Ca2+-activated nonselective cation channel that mediates membrane depolarization. Although, a current with the hallmarks of a TRPM4-mediated current has been previously reported in pancreatic acinar cells (PACs), the role of TRPM4 in the regulation of acinar cell function has not yet been explored. In the present study, we identify this TRPM4 current and describe its role in context of Ca2+ signaling of PACs using pharmacological tools and TRPM4-deficient mice. We found a significant Ca2+-activated cation current in PACs that was sensitive to the TRPM4 inhibitors 9-phenanthrol and 4-chloro-2-[[2-(2-chlorophenoxy)acetyl]amino]benzoic acid (CBA). We demonstrated that the CBA-sensitive current was responsible for a Ca2+-dependent depolarization of PACs from a resting membrane potential of −44.4 ± 2.9 to −27.7 ± 3 mV. Furthermore, we showed that Ca2+ influx was higher in the TRPM4 KO- and CBA-treated PACs than in control cells. As hormone-induced repetitive Ca2+ transients partially rely on Ca2+ influx in PACs, the role of TRPM4 was also assessed on Ca2+ oscillations elicited by physiologically relevant concentrations of the cholecystokinin analog cerulein. These data show that the amplitude of Ca2+ signals was significantly higher in TRPM4 KO than in control PACs. Our results suggest that PACs are depolarized by TRPM4 currents to an extent that results in a significant reduction of the inward driving force for Ca2+. In conclusion, TRPM4 links intracellular Ca2+ signaling to membrane potential as a negative feedback regulator of Ca2+ entry in PACs.
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Affiliation(s)
- Gyula Diszházi
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Zsuzsanna É Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Erika Lisztes
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Edit Tóth-Molnár
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - Péter P Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Rudi Vennekens
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, Faculty of Medicine, TRP Research Platform Leuven, VIB Center for Brain and Disease Research, KU Leuven, Leuven, Belgium
| | - Balázs I Tóth
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
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Skaliczki M, Lukács B, Magyar ZÉ, Kovács T, Bárdi M, Novák S, Diszházi G, Sárközi S, Márton I, Péli-Szabó J, Jóna I, Nánási P, Almássy J. 4-chloro-orto-cresol activates ryanodine receptor more selectively and potently than 4-chloro-meta-cresol. Cell Calcium 2020; 88:102213. [PMID: 32408025 DOI: 10.1016/j.ceca.2020.102213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 04/25/2020] [Accepted: 04/25/2020] [Indexed: 10/24/2022]
Abstract
In this study we performed the comprehensive pharmacological analysis of two stereoisomers of 4-chloro-meta-cresol (4CMC), a popular ryanodine receptor (RyR) agonist used in muscle research. Experiments investigating the Ca2+-releasing action of the isomers demonstrated that the most potent isomer was 4-chloro-orto-cresol (4COC) (EC50 = 55 ± 14 μM), although 3-chloro-para-cresol (3CPC) was more effective, as it was able to induce higher magnitude of Ca2+ flux from isolated terminal cisterna vesicles. Nevertheless, 3CPC stimulated the hydrolytic activity of the sarcoplasmic reticulum ATP-ase (SERCA) with an EC50 of 91 ± 17 μM, while 4COC affected SERCA only in the millimolar range (IC50 = 1370 ± 88 μM). IC50 of 4CMC for SERCA pump was 167 ± 8 μM, indicating that 4CMC is not a specific RyR agonist either, as it activated RyR in a similar concentration (EC50 = 121 ± 20 μM). Our data suggest that the use of 4COC might be more beneficial than 4CMC in experiments, when Ca2+ release should be triggered through RyRs without influencing SERCA activity.
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Affiliation(s)
- Mariann Skaliczki
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary; Department of Dentistry, University of Debrecen, Debrecen, Hungary
| | - Balázs Lukács
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary
| | - Zsuzsanna É Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary
| | - Tünde Kovács
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary
| | - Miklós Bárdi
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary
| | - Szabolcs Novák
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary
| | - Gyula Diszházi
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary
| | - Sándor Sárközi
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary
| | - Ildikó Márton
- Department of Dentistry, University of Debrecen, Debrecen, Hungary
| | - Judit Péli-Szabó
- Medical Imaging Department, Division of Nuclear Medicine, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary
| | - István Jóna
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary; Research Center for Molecular Medicine, University of Debrecen, Faculty of Medicine, 98. Nagyerdei krt. PO Box: 72, Debrecen 4012, Hungary
| | - Péter Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary; Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 98. Nagyerdei krt, Debrecen, Hungary.
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Fanczal J, Pallagi P, Görög M, Diszházi G, Almássy J, Madácsy T, Varga Á, Csernay-Biró P, Katona X, Tóth E, Molnár R, Rakonczay Z, Hegyi P, Maléth J. TRPM2-mediated extracellular Ca 2+ entry promotes acinar cell necrosis in biliary acute pancreatitis. J Physiol 2020; 598:1253-1270. [PMID: 31917868 DOI: 10.1113/jp279047] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/24/2019] [Indexed: 01/05/2023] Open
Abstract
KEY POINTS Acute biliary pancreatitis is a significant clinical challenge as currently no specific pharmaceutical treatment exists. Intracellular Ca2+ overload, increased reactive oxygen species (ROS) production, mitochondrial damage and intra-acinar digestive enzyme activation caused by bile acids are hallmarks of acute biliary pancreatitis. Transient receptor potential melastatin 2 (TRPM2) is a non-selective cation channel that has recently emerged as an important contributor to oxidative-stress-induced cellular Ca2+ overload across different diseases. We demonstrated that TRPM2 is expressed in the plasma membrane of mouse pancreatic acinar and ductal cells, which can be activated by increased oxidative stress induced by H2 O2 treatment and contributed to bile acid-induced extracellular Ca2+ influx in acinar cells, which promoted acinar cell necrosis in vitro and in vivo. These results suggest that the inhibition of TRPM2 may be a potential treatment option for biliary pancreatitis. ABSTRACT Acute biliary pancreatitis poses a significant clinical challenge as currently no specific pharmaceutical treatment exists. Disturbed intracellular Ca2+ signalling caused by bile acids is a hallmark of the disease, which induces increased reactive oxygen species (ROS) production, mitochondrial damage, intra-acinar digestive enzyme activation and cell death. Because of this mechanism of action, prevention of toxic cellular Ca2+ overload is a promising therapeutic target. Transient receptor potential melastatin 2 (TRPM2) is a non-selective cation channel that has recently emerged as an important contributor to oxidative-stress-induced cellular Ca2+ overload across different diseases. However, the expression and possible functions of TRPM2 in the exocrine pancreas remain unknown. Here we found that TRPM2 is expressed in the plasma membrane of mouse pancreatic acinar and ductal cells, which can be activated by increased oxidative stress induced by H2 O2 treatment. TRPM2 activity was found to contribute to bile acid-induced extracellular Ca2+ influx in acinar cells, but did not have the same effect in ductal cells. The generation of intracellular ROS in response to bile acids was remarkably higher in pancreatic acinar cells compared to isolated ducts, which can explain the difference between acinar and ductal cells. This activity promoted acinar cell necrosis in vitro independently from mitochondrial damage or mitochondrial fragmentation. In addition, bile-acid-induced experimental pancreatitis was less severe in TRPM2 knockout mice, whereas the lack of TRPM2 had no protective effect in cerulein-induced acute pancreatitis. Our results suggest that the inhibition of TRPM2 may be a potential treatment option for biliary pancreatitis.
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Affiliation(s)
- Júlia Fanczal
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary
| | - Petra Pallagi
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary.,HAS-USZ Momentum Epithelial Cell Signalling and Secretion Research Group, University of Szeged, Szeged, Hungary
| | - Marietta Görög
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary.,HAS-USZ Momentum Epithelial Cell Signalling and Secretion Research Group, University of Szeged, Szeged, Hungary
| | - Gyula Diszházi
- Department of Physiology, University of Debrecen, Debrecen, Hungary
| | - János Almássy
- Department of Physiology, University of Debrecen, Debrecen, Hungary
| | - Tamara Madácsy
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary.,HAS-USZ Momentum Epithelial Cell Signalling and Secretion Research Group, University of Szeged, Szeged, Hungary
| | - Árpád Varga
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary.,HAS-USZ Momentum Epithelial Cell Signalling and Secretion Research Group, University of Szeged, Szeged, Hungary
| | - Péter Csernay-Biró
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary
| | - Xénia Katona
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary.,HAS-USZ Momentum Epithelial Cell Signalling and Secretion Research Group, University of Szeged, Szeged, Hungary
| | - Emese Tóth
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary
| | - Réka Molnár
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary
| | - Zoltán Rakonczay
- Department of Pathophysiology, University of Szeged, Szeged, Hungary
| | - Péter Hegyi
- HAS-USZ Momentum Translational Gastroenterology Research Group, University of Szeged, Szeged, Hungary.,Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary
| | - József Maléth
- First Department of Internal Medicine, University of Szeged, Szeged, Hungary.,HAS-USZ Momentum Epithelial Cell Signalling and Secretion Research Group, University of Szeged, Szeged, Hungary.,Department of Public Health, University of Szeged, Szeged, Hungary
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Diszházi G, Magyar ZÉ, Mótyán JA, Csernoch L, Jóna I, Nánási PP, Almássy J. Dantrolene Requires Mg 2+ and ATP To Inhibit the Ryanodine Receptor. Mol Pharmacol 2019; 96:401-407. [PMID: 31337666 DOI: 10.1124/mol.119.116475] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 07/07/2019] [Indexed: 12/15/2022] Open
Abstract
Dantrolene is a ryanodine receptor (RyR) inhibitor, which is used to relax muscles in malignant hyperthermia syndrome. Although dantrolene binds to the RyR protein, its mechanism of action is unknown, mainly because of the controversial results showing that dantrolene inhibited Ca2+ release from intact fibers and sarcoplasmic reticulum (SR) vesicles, but failed to inhibit single RyR channel currents in bilayers. Accordingly, it was concluded that an important factor for dantrolene's action was lost during the purification procedure of RyR. Recently, Mg2+ was demonstrated to be the essential factor for dantrolene to inhibit Ca2+ release in skinned muscle fibers. The aim of the present study was to confirm these results in Ca2+ release and bilayer experiments, using SR vesicles and solubilized channels, respectively. Our Ca2+ release experiments demonstrated that the effect of dantrolene and Mg2+ was cooperative and that ATP enhanced the inhibiting effect of dantrolene. Namely, 10 µM dantrolene reduced RyR channel open probability by ∼50% in the presence of 3 mM free Mg2+ and 1 mM ATP, whereas channel activity further decreased to ∼20% of control when [ATP] was increased to 2 mM. Our data provide important complementary information that supports the direct, Mg2+-dependent mechanism of dantrolene's action and suggests that dantrolene also requires ATP to inhibit RyR.
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Affiliation(s)
- Gyula Diszházi
- Departments of Physiology (G.D., Z.É.M., L.C., P.P.N., J.A.) and Biochemistry and Molecular Biology (J.A.M.), and Research Centre for Molecular Medicine (I.J.), Faculty of Medicine, and Department of Dental Physiology and Pharmacology, Faculty of Dentistry (P.P.N.), University of Debrecen, Debrecen, Hungary
| | - Zsuzsanna Édua Magyar
- Departments of Physiology (G.D., Z.É.M., L.C., P.P.N., J.A.) and Biochemistry and Molecular Biology (J.A.M.), and Research Centre for Molecular Medicine (I.J.), Faculty of Medicine, and Department of Dental Physiology and Pharmacology, Faculty of Dentistry (P.P.N.), University of Debrecen, Debrecen, Hungary
| | - János András Mótyán
- Departments of Physiology (G.D., Z.É.M., L.C., P.P.N., J.A.) and Biochemistry and Molecular Biology (J.A.M.), and Research Centre for Molecular Medicine (I.J.), Faculty of Medicine, and Department of Dental Physiology and Pharmacology, Faculty of Dentistry (P.P.N.), University of Debrecen, Debrecen, Hungary
| | - László Csernoch
- Departments of Physiology (G.D., Z.É.M., L.C., P.P.N., J.A.) and Biochemistry and Molecular Biology (J.A.M.), and Research Centre for Molecular Medicine (I.J.), Faculty of Medicine, and Department of Dental Physiology and Pharmacology, Faculty of Dentistry (P.P.N.), University of Debrecen, Debrecen, Hungary
| | - István Jóna
- Departments of Physiology (G.D., Z.É.M., L.C., P.P.N., J.A.) and Biochemistry and Molecular Biology (J.A.M.), and Research Centre for Molecular Medicine (I.J.), Faculty of Medicine, and Department of Dental Physiology and Pharmacology, Faculty of Dentistry (P.P.N.), University of Debrecen, Debrecen, Hungary
| | - Péter Pál Nánási
- Departments of Physiology (G.D., Z.É.M., L.C., P.P.N., J.A.) and Biochemistry and Molecular Biology (J.A.M.), and Research Centre for Molecular Medicine (I.J.), Faculty of Medicine, and Department of Dental Physiology and Pharmacology, Faculty of Dentistry (P.P.N.), University of Debrecen, Debrecen, Hungary
| | - János Almássy
- Departments of Physiology (G.D., Z.É.M., L.C., P.P.N., J.A.) and Biochemistry and Molecular Biology (J.A.M.), and Research Centre for Molecular Medicine (I.J.), Faculty of Medicine, and Department of Dental Physiology and Pharmacology, Faculty of Dentistry (P.P.N.), University of Debrecen, Debrecen, Hungary
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Magyar ZÉ, Diszházi G, Péli-Szabó J, Szentesi P, Collet C, Csernoch L, Nánási P, Almássy J. The diamide insecticide chlorantraniliprole increases the single-channel current activity of the mammalian skeletal muscle ryanodine receptor. Gen Physiol Biophys 2019; 38:183-186. [PMID: 30821253 DOI: 10.4149/gpb_2019007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 02/15/2019] [Indexed: 11/08/2022]
Abstract
Very recently, the diamide insecticide chlorantraniliprole was shown to induce Ca2+-release from sarcoplasmic reticulum (SR) vesicles isolated from mammalian skeletal muscle through the activation of the SR Ca2+ channel ryanodine receptor. As this result raises severe concerns about the safety of this chemical, we aimed to learn more about its action. To this end, single-channel analysis was performed, which showed that chlorantraniliprole induced high-activity bursts of channel opening that accounts for the Ca2+-releasing action described before.
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Affiliation(s)
- Zsuzsanna É Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
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Almássy J, Diszházi G, Skaliczki M, Márton I, Magyar ZÉ, Nánási PP, Yule DI. Expression of BK channels and Na +-K + pumps in the apical membrane of lacrimal acinar cells suggests a new molecular mechanism for primary tear-secretion. Ocul Surf 2019; 17:272-277. [PMID: 30685438 DOI: 10.1016/j.jtos.2019.01.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 01/16/2019] [Accepted: 01/23/2019] [Indexed: 11/30/2022]
Abstract
PURPOSE Primary fluid secretion in secretory epithelia relies on the unidirectional transport of ions and water across a single cell layer. This mechanism requires the asymmetric apico-basal distribution of ion transporters and intracellular Ca2+ signaling. The primary aim of the present study was to verify the localization and the identity of Ca2+-dependent ion channels in acinar cells of the mouse lacrimal gland. METHODS Whole-cell patch-clamp-electrophysiology, spatially localized flash-photolysis of Ca2+ and temporally resolved digital Ca2+-imaging was combined. Immunostaining of enzymatically isolated mouse lacrimal acinar cells was performed. RESULTS We show that the Ca2+-dependent K+-conductance is paxilline-sensitive, abundant in the luminal, but negligible in the basal membrane; and co-localizes with Cl--conductance. These data suggest that both Cl- and K+ are secreted into the lumen and thus they account for the high luminal [Cl-] (∼141 mM), but not for the relatively low [K+] (<17 mM) of the primary fluid. Accordingly, these results also imply that K+ must be reabsorbed from the primary tear fluid by the acinar cells. We hypothesized that apically-localized Na+-K+ pumps are responsible for K+-reabsorption. To test this possibility, immunostaining of lacrimal acinar cells was performed using anti-Na+-K+ ATP-ase antibody. We found positive fluorescence signal not only in the basal, but in the apical membrane of acinar cells too. CONCLUSIONS Based on these results we propose a new primary fluid-secretion model in the lacrimal gland, in which the paracellular pathway of Na+ secretion is supplemented by a transcellular pathway driven by apical Na+-K+ pumps.
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Affiliation(s)
- János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
| | - Gyula Diszházi
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Marianna Skaliczki
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary; Department of Dentistry, University of Debrecen, Debrecen, Hungary
| | - Ildikó Márton
- Department of Dentistry, University of Debrecen, Debrecen, Hungary
| | - Zsuzsanna Édua Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Péter P Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - David I Yule
- Department of Pharmacology and Physiology and the Centre for Oral Biology, University of Rochester, Medical Center, Rochester, USA
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Vincze J, Geyer N, Diszházi G, Csernoch L, Bíró T, Jóna I, Dienes B, Almássy J. Laser induced calcium oscillations in fluorescent calcium imaging. Gen Physiol Biophys 2018; 37:253-261. [PMID: 29589836 DOI: 10.4149/gpb_2017054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 11/02/2017] [Indexed: 11/08/2022]
Abstract
Phototoxicity is the most common problem investigators may encounter when performing live cell imaging. It develops due to excess laser exposure of cells loaded with fluorophores and can lead to often overlooked but significant artifacts, such as massive increase of intracellular Ca2+ concentration, which would make data interpretation problematic. Because information about laser- and dye-related changes in cytoplasmic calcium concentration is very limited, we aimed to describe this phenomenon to help investigators using laser scanning confocal microscopy in a non-invasive way. Therefore, in the present study we evaluated fluorescent fluctuations, which evolved in Fluo-3/4/8 loaded mouse pancreatic acinar cells during very low intensity laser excitation. We demonstrate that after standard loading procedure (2 µM Fluo-3/4/8-AM, 30 min at room temperature), applying 488 nm laser at as low as ca. 10 µW incident laser power (0.18 µW/µm2) at 1 Hz caused repetitive, 2-3 fold elevations of the resting intracellular fluorescence. The first latency and the pattern of the fluorescence fluctuations were laser power dependent and were related to Ca2+-release from intracellular stores, as they were abolished by BAPTA-AM treatment in Ca2+-free medium, but were not diminished by the reactive oxygen species (ROS) scavenger DMPO. Worryingly enough, the qualitative and quantitative features of the Ca2+-waves were practically indistinguishable from the responses evoked by secretagogue stimulation. Since using similar imaging conditions, a number of other cell types were reported to display spontaneous Ca2+ oscillations, we propose strategies to distinguish the real signals from artifacts.
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Affiliation(s)
- János Vincze
- Department of Physiology, University of Debrecen, Faculty of Medicine, 98. Nagyerdei krt., Debrecen 4012, Hungary.
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Geyer N, Diszházi G, Csernoch L, Jóna I, Almássy J. Bile acids activate ryanodine receptors in pancreatic acinar cells via a direct allosteric mechanism. Cell Calcium 2015; 58:160-70. [DOI: 10.1016/j.ceca.2015.03.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 03/10/2015] [Accepted: 03/30/2015] [Indexed: 12/12/2022]
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