scholarly journals Expression and subcellular localization of the ryanodine receptor in rat pancreatic acinar cells

1999 ◽  
Vol 337 (2) ◽  
pp. 305-309 ◽  
Author(s):  
M. Fatima LEITE ◽  
Jonathan A. DRANOFF ◽  
Ling GAO ◽  
Michael H. NATHANSON
Keyword(s):  
Ryanodine Receptor ◽  
Acinar Cell ◽  
Acinar Cells ◽  
Pancreatic Acinar Cells ◽  
Apical Region ◽  
Cell Type ◽  
Excitable Cells ◽  
Release Channel ◽  
Trigger Zone

The ryanodine receptor (RyR) is the principal Ca2+-release channel in excitable cells, whereas the inositol 1,4,5-trisphosphate (InsP3) receptor (InsP3R) is primarily responsible for Ca2+ release in non-excitable cells, including epithelia. RyR also is expressed in a number of non-excitable cell types, but is thought to serve as an auxiliary or alternative Ca2+-release pathway in those cells. Here we use reverse transcription PCR to show that a polarized epithelium, the pancreatic acinar cell, expresses the type 2, but not the type 1 or 3, isoform of RyR. We furthermore use immunochemistry to demonstrate that the type 2 RyR is distributed throughout the basolateral and, to a lesser extent, the apical region of the acinar cell, but is excluded from the trigger zone, where cytosolic Ca2+ signals originate in this cell type. Since propagation of Ca2+ waves in acinar cells is sensitive to ryanodine, caffeine and Ca2+, these findings suggest that Ca2+ waves in this cell type result from the co-ordinated release of Ca2+, first from InsP3Rs in the trigger zone, then from RyRs elsewhere in the cell. RyR may play a fundamental role in Ca2+ signalling in polarized epithelia, including for Ca2+ signals initiated by InsP3.

scholarly journals The ryanodine receptor is expressed in human pancreatic acinar cells and contributes to acinar cell injury

2014 ◽  
Vol 307 (5) ◽  
pp. G574-G581 ◽  
Author(s):  
Christopher M. Lewarchik ◽  
Abrahim I. Orabi ◽  
Shunqian Jin ◽  
Dong Wang ◽  
Kamaldeen A. Muili ◽  
...  
Keyword(s):  
Ryanodine Receptor ◽  
Acinar Cell ◽  
Cell Injury ◽  
Acinar Cells ◽  
Pancreatic Tissue ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Muscarinic Agonist ◽  
Basal Region ◽  
Release Channel

Physiological calcium (Ca2+) signals within the pancreatic acinar cell regulate enzyme secretion, whereas aberrant Ca2+ signals are associated with acinar cell injury. We have previously identified the ryanodine receptor (RyR), a Ca2+ release channel on the endoplasmic reticulum, as a modulator of these pathological signals. In the present study, we establish that the RyR is expressed in human acinar cells and mediates acinar cell injury. We obtained pancreatic tissue from cadaveric donors and identified isoforms of RyR1 and RyR2 by qPCR. Immunofluorescence staining of the pancreas showed that the RyR is localized to the basal region of the acinar cell. Furthermore, the presence of RyR was confirmed from isolated human acinar cells by tritiated ryanodine binding. To determine whether the RyR is functionally active, mouse or human acinar cells were loaded with the high-affinity Ca2+ dye (Fluo-4 AM) and stimulated with taurolithocholic acid 3-sulfate (TLCS) (500 μM) or carbachol (1 mM). Ryanodine (100 μM) pretreatment reduced the magnitude of the Ca2+ signal and the area under the curve. To determine the effect of RyR blockade on injury, human acinar cells were stimulated with pathological stimuli, the bile acid TLCS (500 μM) or the muscarinic agonist carbachol (1 mM) in the presence or absence of the RyR inhibitor ryanodine. Ryanodine (100 μM) caused an 81% and 47% reduction in acinar cell injury, respectively, as measured by lactate dehydrogenase leakage ( P < 0.05). Taken together, these data establish that the RyR is expressed in human acinar cells and that it modulates acinar Ca2+ signals and cell injury.

Multiple isoforms of the ryanodine receptor are expressed in rat pancreatic acinar cells

2000 ◽  
Vol 351 (1) ◽  
pp. 265-271 ◽  
Author(s):  
Timothy J. FITZSIMMONS ◽  
Ilya GUKOVSKY ◽  
James A. McROBERTS ◽  
Edward RODRIGUEZ ◽  
F. Anthony LAI ◽  
...  
Keyword(s):  
Western Blot ◽  
Ryanodine Receptor ◽  
Acinar Cell ◽  
Acinar Cells ◽  
Protein Band ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Rt Pcr ◽  
Pancreatic Acini ◽  
Cell Functions

Regulation of cytosolic Ca2+ is important for a variety of cell functions. The ryanodine receptor (RyR) is a Ca2+ channel that conducts Ca2+ from internal pools to the cytoplasm. To demonstrate the presence of the RyR in the pancreatic acinar cell, we performed reverse transcriptase (RT)-PCR, Western blot, immunocytochemistry and microscopic Ca2+-release measurements on these cells. RT-PCR showed the presence of mRNA for RyR isoforms 1, 2 and 3 in both rat pancreas and dispersed pancreatic acini. Furthermore, mRNA expression for RyR isoforms 1 and 2 was demonstrated by RT-PCR in individual pancreatic acinar cells selected under the microscope. Western-blot analysis of acinar cell immunoprecipitates, using antibodies against RyR1 and RyR2, showed a high-molecular-mass (> 250kDa) protein band that was much less intense when immunoprecipitated in the presence of RyR peptide. Functionally, permeablized acinar cells stimulated with the RyR activator, palmitoyl-CoA, released Ca2+ from both basolateral and apical regions. These data show that pancreatic acinar cells express multiple isoforms of the RyR and that there are functional receptors throughout the cell.

scholarly journals Cluster of Differentiation 38 (CD38) Mediates Bile Acid-induced Acinar Cell Injury and Pancreatitis through Cyclic ADP-ribose and Intracellular Calcium Release

2013 ◽  
Vol 288 (38) ◽  
pp. 27128-27137 ◽  
Author(s):  
Abrahim I. Orabi ◽  
Kamaldeen A. Muili ◽  
Tanveer A. Javed ◽  
Shunqian Jin ◽  
Thottala Jayaraman ◽  
...  
Keyword(s):  
Bile Acid ◽  
Ryanodine Receptor ◽  
Acinar Cell ◽  
Calcium Release ◽  
Cell Injury ◽  
Acinar Cells ◽  
Pancreatic Acinar Cells ◽  
Iodide Uptake ◽  
Cyclic Adp Ribose ◽  
Intracellular Ca

Aberrant Ca2+ signals within pancreatic acinar cells are an early and critical feature in acute pancreatitis, yet it is unclear how these signals are generated. An important mediator of the aberrant Ca2+ signals due to bile acid exposure is the intracellular Ca2+ channel ryanodine receptor. One putative activator of the ryanodine receptor is the nucleotide second messenger cyclic ADP-ribose (cADPR), which is generated by an ectoenzyme ADP-ribosyl cyclase, CD38. In this study, we examined the role of CD38 and cADPR in acinar cell Ca2+ signals and acinar injury due to bile acids using pharmacologic inhibitors of CD38 and cADPR as well as mice deficient in Cd38 (Cd38−/−). Cytosolic Ca2+ signals were imaged using live time-lapse confocal microscopy in freshly isolated mouse acinar cells during perifusion with the bile acid taurolithocholic acid 3-sulfate (TLCS; 500 μm). To focus on intracellular Ca2+ release and to specifically exclude Ca2+ influx, cells were perifused in Ca2+-free medium. Cell injury was assessed by lactate dehydrogenase leakage and propidium iodide uptake. Pretreatment with either nicotinamide (20 mm) or the cADPR antagonist 8-Br-cADPR (30 μm) abrogated TLCS-induced Ca2+ signals and cell injury. TLCS-induced Ca2+ release and cell injury were reduced by 30 and 95%, respectively, in Cd38-deficient acinar cells compared with wild-type cells (p < 0.05). Cd38-deficient mice were protected against a model of bile acid infusion pancreatitis. In summary, these data indicate that CD38-cADPR mediates bile acid-induced pancreatitis and acinar cell injury through aberrant intracellular Ca2+ signaling.

scholarly journals Evidence for secretion-like coupling involving pp60src in the activation and maintenance of store-mediated Ca2+ entry in mouse pancreatic acinar cells

2003 ◽  
Vol 370 (1) ◽  
pp. 255-263 ◽  
Author(s):  
Pedro C. REDONDO ◽  
Ana I. LAJAS ◽  
Ginés M. SALIDO ◽  
Antonio GONZALEZ ◽  
Juan A. ROSADO ◽  
...  
Keyword(s):  
Actin Cytoskeleton ◽  
Acinar Cells ◽  
Coupling Model ◽  
Pancreatic Acinar Cells ◽  
Coupling Mechanism ◽  
Cell Type ◽  
Cortical Actin ◽  
Excitable Cells ◽  
Latrunculin A

Store-mediated Ca2+ entry (SMCE) is one of the main pathways for Ca2+ influx in non-excitable cells. Recent studies favour a secretion-like coupling mechanism to explain SMCE, where Ca2+ entry is mediated by an interaction of the endoplasmic reticulum (ER) with the plasma membrane (PM) and is modulated by the actin cytoskeleton. To explore this possibility further we have now investigated the role of the actin cytoskeleton in the activation and maintenance of SMCE in pancreatic acinar cells, a more specialized secretory cell type which might be an ideal cellular model to investigate further the properties of the secretion-like coupling model. In these cells, the cytoskeletal disrupters cytochalasin D and latrunculin A inhibited both the activation and maintenance of SMCE. In addition, stabilization of a cortical actin barrier by jasplakinolide prevented the activation, but not the maintenance, of SMCE, suggesting that, as for secretion, the actin cytoskeleton plays a double role in SMCE as a negative modulator of the interaction between the ER and PM, but is also required for this mechanism, since the cytoskeleton disrupters impaired Ca2+ entry. Finally, depletion of the intracellular Ca2+ stores induces cytoskeletal association and activation of pp60src, which is independent on Ca2+ entry. pp60src activation requires the integrity of the actin cytoskeleton and participates in the initial phase of the activation of SMCE in pancreatic acinar cells.

Su1899 The Ryanodine Receptor is Expressed in Mouse and Human Pancreatic Acinar Cells and Contributes to Acinar Cell Injury

2014 ◽  
Vol 146 (5) ◽  
pp. S-496
Author(s):  
Chris M. Lewarchik ◽  
Shunqian Jin ◽  
Dong Wang ◽  
Abrahim I. Orabi ◽  
Kamaldeen A. Muili ◽  
...  
Keyword(s):  
Ryanodine Receptor ◽  
Acinar Cell ◽  
Cell Injury ◽  
Acinar Cells ◽  
Pancreatic Acinar Cells

ETHANOL SENSITIZES PANCREATIC ACINAR CELLS TO CARBACHOL-INDUCED PROTEASE ACTIVATION VIA THE RYANODINE RECEPTOR

Pancreas ◽  
2008 ◽  
Vol 37 (4) ◽  
pp. 495
Author(s):  
A. U. Shah ◽  
A. Orabi ◽  
A. U. Shah ◽  
Z. M. Mannan ◽  
S. Z. Husain
Keyword(s):  
Ryanodine Receptor ◽  
Acinar Cells ◽  
Pancreatic Acinar Cells ◽  
Protease Activation

scholarly journals Localized Ca2+ uncaging reveals polarized distribution of Ca2+-sensitive Ca2+ release sites

2002 ◽  
Vol 158 (2) ◽  
pp. 283-292 ◽  
Author(s):  
Michael C. Ashby ◽  
Madeleine Craske ◽  
Myoung Kyu Park ◽  
Oleg V. Gerasimenko ◽  
Robert D. Burgoyne ◽  
...  
Keyword(s):  
Ryanodine Receptors ◽  
Acinar Cells ◽  
Cell Types ◽  
Pancreatic Acinar Cells ◽  
Apical Region ◽  
Basal Region ◽  
Activation Pattern ◽  
Inositol Trisphosphate Receptors ◽  
Agonist Stimulation ◽  
Major Process

Ca2+-induced Ca2+ release (CICR) plays an important role in the generation of cytosolic Ca2+ signals in many cell types. However, it is inherently difficult to distinguish experimentally between the contributions of messenger-induced Ca2+ release and CICR. We have directly tested the CICR sensitivity of different regions of intact pancreatic acinar cells using local uncaging of caged Ca2+. In the apical region, local uncaging of Ca2+ was able to trigger a CICR wave, which propagated toward the base. CICR could not be triggered in the basal region, despite the known presence of ryanodine receptors. The triggering of CICR from the apical region was inhibited by a pharmacological block of ryanodine or inositol trisphosphate receptors, indicating that global signals require coordinated Ca2+ release. Subthreshold agonist stimulation increased the probability of triggering CICR by apical uncaging, and uncaging-induced CICR could activate long-lasting Ca2+ oscillations. However, with subthreshold stimulation, CICR could still not be initiated in the basal region. CICR is the major process responsible for global Ca2+ transients, and intracellular variations in sensitivity to CICR predetermine the activation pattern of Ca2+ waves.

Crambene induces pancreatic acinar cell apoptosis via the activation of mitochondrial pathway

2006 ◽  
Vol 291 (1) ◽  
pp. G95-G101 ◽  
Author(s):  
Yang Cao ◽  
Sharmila Adhikari ◽  
Abel Damien Ang ◽  
Marie Véronique Clément ◽  
Matthew Wallig ◽  
...  
Keyword(s):  
Acinar Cell ◽  
Cell Apoptosis ◽  
Caspase 3 ◽  
Fas Ligand ◽  
Annexin V ◽  
Acinar Cells ◽  
Mitochondrial Pathway ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Pancreatic Acini

We investigated the apoptotic pathway activated by crambene (1-cyano-2-hydroxy-3-butene), a plant nitrile, on pancreatic acinar cells. As evidenced by annexin V-FITC staining, crambene treatment for 3 h induced the apoptosis but not necrosis of pancreatic acini. Caspase-3, -8, and -9 activities in acini treated with crambene were significantly higher than in untreated acini. Treatment with caspase-3, -8, and -9 inhibitors inhibited annexin V staining, as well as caspase-3 activity, pointing to an important role of these caspases in crambene-induced acinar cell apoptosis. The mitochondrial membrane potential was collapsed, and cytochrome c was released from the mitochondria in crambene-treated acini. Neither TNF-α nor Fas ligand levels were changed in pancreatic acinar cells after crambene treatment. These results provide evidence for the induction of pancreatic acinar cell apoptosis in vitro by crambene and suggest the involvement of mitochondrial pathway in pancreatic acinar cell apoptosis.

scholarly journals SEC23B is required for pancreatic acinar cell function in adult mice

2017 ◽  
Vol 28 (15) ◽  
pp. 2146-2154 ◽  
Author(s):  
Rami Khoriaty ◽  
Nancy Vogel ◽  
Mark J. Hoenerhoff ◽  
M. Dolors Sans ◽  
Guojing Zhu ◽  
...  
Keyword(s):  
Acinar Cell ◽  
Cell Function ◽  
Acinar Cells ◽  
Cell Loss ◽  
Normal Function ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Total Protein Content ◽  
Pancreatic Cell ◽  
Adult Mice

Mice with germline absence of SEC23B die perinatally, exhibiting massive pancreatic degeneration. We generated mice with tamoxifen-inducible, pancreatic acinar cell–specific Sec23b deletion. Inactivation of Sec23b exclusively in the pancreatic acinar cells of adult mice results in decreased overall pancreatic weights from pancreatic cell loss (decreased pancreatic DNA, RNA, and total protein content), as well as degeneration of exocrine cells, decreased zymogen granules, and alterations in the endoplasmic reticulum (ER), ranging from vesicular ER to markedly expanded cisternae with accumulation of moderate-density content or intracisternal granules. Acinar Sec23b deletion results in induction of ER stress and increased apoptosis in the pancreas, potentially explaining the loss of pancreatic cells and decreased pancreatic weight. These findings demonstrate that SEC23B is required for normal function of pancreatic acinar cells in adult mice.

Sign in / Sign up

Export Citation Format

Share Document