scholarly journals Effect of inositol 1,4,5-trisphosphate receptor stimulation on mitochondrial [Ca2+] and secretion in chromaffin cells

2002 ◽  
Vol 365 (2) ◽  
pp. 451-459 ◽  
Author(s):  
Mayte MONTERO ◽  
Maria Teresa ALONSO ◽  
Almudena ALBILLOS ◽  
Inmaculada CUCHILLO-IBÁÑEZ ◽  
Román OLIVARES ◽  
...  
Keyword(s):  
Chromaffin Cells ◽  
Ryanodine Receptors ◽  
Catecholamine Secretion ◽  
Mitochondrial Inhibitors ◽  
High K ◽  
Inositol 1,4,5 Trisphosphate ◽  
Insp3 Receptors ◽  
Voltage Dependent ◽  
Trisphosphate Receptor ◽  
Stimulation Of

Ca2+ uptake by mitochondria is a potentially important buffering system able to control cytosolic [Ca2+]. In chromaffin cells, we have shown previously that stimulation of either Ca2+ entry or Ca2+ release via ryanodine receptors triggers large increases in mitochondrial [Ca2+] ([Ca2+]M) approaching the millimolar range, whose blockade dramatically enhances catecholamine secretion [Montero, Alonso, Carnicero, Cuchillo-Ibañez, Albillos, Garcia, Carcia-Sancho and Alvarez (2000) Nat. Cell Biol. 2, 57–61]. In the present study, we have studied the effect of stimulation of inositol 1,4,5-trisphosphate (InsP3) receptors using histamine. We find that histamine produces a heterogeneous increase in [Ca2+]M, reaching peak levels at approx. 1μM in 70% of the mitochondrial space to several hundred micromolar in 2–3% of mitochondria. Intermediate levels were found in the rest of the mitochondrial space. Single-cell imaging experiments with aequorin showed that the heterogeneity had both an intercellular and a subcellular origin. Those mitochondria responding to histamine with increases in [Ca2+]M much greater than 1μM (30%) were the same as those that also responded with large increases in [Ca2+]M following stimulation with either high-K+ medium or caffeine. Blocking mitochondrial Ca2+ uptake with protonophores or mitochondrial inhibitors also enhanced catecholamine secretion induced by histamine. These results suggest that some InsP3 receptors tightly co-localize with ryanodine receptors and voltage-dependent Ca2+ channels in defined subplasmalemmal functional units designed to control secretion induced by different stimuli.

scholarly journals Ca2+ entry into PC12 cells initiated by ryanodine receptors or inositol 1,4,5-trisphosphate receptors

1998 ◽  
Vol 329 (2) ◽  
pp. 349-357 ◽  
Author(s):  
L. Deborah BENNETT ◽  
D. Martin BOOTMAN ◽  
J. Michael BERRIDGE ◽  
R. Timothy CHEEK
Keyword(s):  
Endoplasmic Reticulum ◽  
Pc12 Cells ◽  
Ryanodine Receptors ◽  
Half Time ◽  
Free Medium ◽  
Excitable Cells ◽  
Inositol 1,4,5 Trisphosphate ◽  
Insp3 Receptors ◽  
Universal Mechanism ◽  
Stimulation Of

Capacitative Ca2+ entry (CCE) is a universal mechanism for refilling intracellular Ca2+ stores in electrically non-excitable cells. The situation in excitable cells is less clear, however, since they may rely on other entry mechanisms for Ca2+-store refilling. In the present study we investigated CCE in intact PC12 cells, using acetylcholine to bring about activation of InsP3 receptors (InsP3Rs), caffeine to activate ryanodine receptors (RyRs) and thapsigargin to inhibit sarco/endoplasmic reticulum Ca2+-ATPase pumps. We found that depletion of the InsP3-, caffeine- or thapsigargin-sensitive stores promoted Ca2+ entry, suggesting that stimulation of either InsP3Rs or RyRs can activate CCE. The CCE pathways activated by InsP3Rs, RyRs and thapsigargin appeared to be independent at least in part, since their effects were found to be additive. However, CCE triggered by caffeine, acetylcholine or thapsigargin progressively diminished with time. The decay of CCE caused by one agent also inhibited subsequent responses to the others, suggesting that some component of the CCE pathway is common to all intracellular Ca2+ stores. The magnitude of CCE stimulated by InsP3Rs or RyRs was related to the size of the stores; the InsP3-sensitive store was smaller than the RyR-sensitive store and triggered a smaller entry component. However, both stores filled with a similar half time (about 1 min), and both could be filled more rapidly by depolarization-induced Ca2+ entry through voltage-operated channels. A significant basal Ca2+ influx was apparent in PC12 cells. The basal entry component may be under the control of the InsP3-sensitive Ca2+ store, since short incubations in Ca2+-free medium depleted this store.

scholarly journals Caffeine-induced inhibition of inositol(1,4,5)-trisphosphate-gated calcium channels from cerebellum.

1994 ◽  
Vol 5 (1) ◽  
pp. 97-103 ◽  
Author(s):  
I Bezprozvanny ◽  
S Bezprozvannaya ◽  
B E Ehrlich
Keyword(s):  
Lipid Bilayers ◽  
Inhibitory Action ◽  
Single Channel ◽  
Ryanodine Receptors ◽  
Single Channels ◽  
Ca Channels ◽  
Open Time ◽  
Inositol 1,4,5 Trisphosphate ◽  
Insp3 Receptors ◽  
Intracellular Ca

Effects of the xanthine drug caffeine on inositol (1,4,5)-trisphosphate (InsP3)-gated calcium (Ca) channels from canine cerebellum were studied using single channels incorporated into planar lipid bilayers. Caffeine, used widely as an agonist of ryanodine receptors, inhibited the activity of InsP3-gated Ca channels in a noncooperative fashion with half-inhibition at 1.64 mM caffeine. The frequency of channel openings was decreased more than threefold after addition of 5 mM caffeine; there was only a small effect on mean open time of the channels, and the single channel conductance was unchanged. Increased InsP3 concentration overcame the inhibitory action of caffeine, but caffeine did not reduce specific [3H]InsP3 binding to the receptor. The inhibitory action of caffeine on InsP3 receptors suggests that the action of caffeine on the intracellular Ca pool must be interpreted with caution when both ryanodine receptors and InsP3 receptors are present in the cell.

Different contributions of L- and Q-type Ca2+ channels to Ca2+ signals and secretion in chromaffin cell subtypes

1997 ◽  
Vol 272 (2) ◽  
pp. C476-C484 ◽  
Author(s):  
R. B. Lomax ◽  
P. Michelena ◽  
L. Nunez ◽  
J. Garcia-Sancho ◽  
A. G. Garcia ◽  
...  
Keyword(s):  
Chromaffin Cells ◽  
Chromaffin Cell ◽  
Channel Blocker ◽  
Cell Types ◽  
Bay K 8644 ◽  
High K ◽  
Voltage Dependent ◽  
Bovine Chromaffin Cells ◽  
P Type ◽  
Ca2 Channels

In this study, we investigated the contribution of different subtypes of voltage-dependent Ca2+ channels to changes in cytosolic free Ca2+ ([Ca2+]i) and secretion in noradrenergic and adrenergic bovine chromaffin cells. In single immunocytochemically identified chromaffin cells, [Ca2+]i increased transiently during high K+ depolarization. Furnidipine and BAY K 8644, L-type Ca2+ channel blocker and activator, respectively, affected the [Ca2+]i rise more in noradrenergic than in adrenergic cells. In contrast, the Q-type Ca2+ channel blocker omega-conotoxin MVIIC inhibited the [Ca2+]i rise more in adrenergic cells. omega-Agatoxin IVA (30 nM), which blocks P-type Ca2+ channels, had little effect on the [Ca2+]i signal. The N-type Ca2+ channel blocker omega-conotoxin GVIA similarly inhibited the [Ca2+]i rise in both cell types. The effects of furnidipine, BAY K 8644, and omega-conotoxin MVIIC on K+-evoked norepinephrine and epinephrine release paralleled those effects on [Ca2+]i signals. However, omega-conotoxin GVIA and 30 nM omega-agatoxin IVA did not affect the secretion of either amine. The data suggest that, in the bovine adrenal medulla, the release of epinephrine and norepinephrine are preferentially controlled by Q- and L-type Ca2+ channels, respectively. P- and N-type Ca2+ channels do not seem to control the secretion of either catecholamine.

Moving Ca2+ from the endoplasmic reticulum to mitochondria: is spatial intimacy enough?

2006 ◽  
Vol 34 (3) ◽  
pp. 351-355 ◽  
Author(s):  
G.A. Rutter
Keyword(s):  
Endoplasmic Reticulum ◽  
Outer Membrane Proteins ◽  
Anion Channel ◽  
Mitochondrial Outer Membrane ◽  
Interconnected Network ◽  
Voltage Dependent Anion Channel ◽  
Permeabilized Cells ◽  
Inositol 1,4,5 Trisphosphate ◽  
Voltage Dependent ◽  
Trisphosphate Receptor

A number of studies in recent years have demonstrated that the ER (endoplasmic reticulum) makes intimate contacts with mitochondria, the latter organelles existing both as individual organelles and occasionally as a more extensive interconnected network. Demonstrations that mitochondria take up Ca2+ more avidly upon its mobilization from the ER than when delivered to permeabilized cells as a buffered solution also indicate that a shielded conduit for Ca2+ may exist between the two organelle types, perhaps comprising the inositol 1,4,5-trisphosphate receptor and mitochondrial outer membrane proteins including the VDAC (voltage-dependent anion channel). Although the existence of such intracellular ER–mitochondria ‘synapses’, or of an ER–mitochondria Ca2+ ‘translocon’, is an exciting idea, more definitive experiments are needed to test this possibility.

scholarly journals Control of inositol 1,4,5-trisphosphate-induced Ca2+ release by cytosolic Ca2+

1995 ◽  
Vol 306 (2) ◽  
pp. 445-451 ◽  
Author(s):  
M D Bootman ◽  
L Missiaen ◽  
J B Parys ◽  
H De Smedt ◽  
R Casteels
Keyword(s):  
Binding Site ◽  
Cell Types ◽  
Inhibitory Effects ◽  
Activation Curve ◽  
Hormonal Stimulation ◽  
A7r5 Cells ◽  
Inositol 1,4,5 Trisphosphate ◽  
Insp3 Receptors ◽  
Dependent Inhibition ◽  
Stimulation Of

The synergistic action of cytosolic Ca2+ and inositol 1,4,5-trisphosphate (InsP3) in releasing intracellular Ca2+ stores has been suggested to be responsible for the complex intracellular Ca2 signals observed during hormonal stimulation of many cell types. However, the ability of cytosolic Ca2+ to potentiate Ca2+ release has recently been questioned because of the observed inhibitory effects of Ca2+ chelators used in previous studies. In the present study, EGTA and BAPTA [1,2-bis-(2-amino-phenoxy)ethane- NNN'N′-tetra-acetic acid] poorly inhibited InsP3-induced Ca2+ release from permeabilized A7r5 smooth-muscle cells. Additionally, stimulatory effects of cytosolic and luminal Ca2+ were observed either in the complete absence of Ca2+ chelator or at constant Ca(2+)-free chelator concentration. These data suggest that potentiation of InsP3-induced Ca2+ release by Ca2+ in A7r5 cells reflects an interaction between Ca2+ and InsP3 receptors, rather than a decrease in chelator-dependent inhibition. The EC50 for activation of InsP3-induced Ca2+ release by cytosolic Ca2+ was unaffected by ATP, or by changing InsP3 concentration, although InsP3-induced Ca2+ release became less sensitive to the inhibitory effects of cytosolic Ca2+ as the InsP3 concentration was elevated. Increasing H+ or Mg2+ concentration shifted the Ca(2+)-activation curve towards higher Ca2+ concentrations. These data suggest that, in addition to the InsP3-binding site, the affinity of the Ca(2+)-binding site(s) on InsP3 receptors can be modulated by intracellular cations.

scholarly journals Annexin II in exocytosis: catecholamine secretion requires the translocation of p36 to the subplasmalemmal region in chromaffin cells.

1996 ◽  
Vol 133 (6) ◽  
pp. 1217-1236 ◽  
Author(s):  
S Chasserot-Golaz ◽  
N Vitale ◽  
I Sagot ◽  
B Delouche ◽  
S Dirrig ◽  
...  
Keyword(s):  
Chromaffin Cells ◽  
Insoluble Fraction ◽  
Catecholamine Secretion ◽  
Annexin Ii ◽  
Cell Periphery ◽  
High K ◽  
Confocal Immunofluorescence ◽  
S 100 ◽  
Triton X ◽  
Insoluble Protein Fraction

Annexin II is a Ca(2+)-dependent membrane-binding protein present in a wide variety of cells and tissues. Within cells, annexin II is found either as a 36-kD monomer (p36) or as a heterotetrameric complex (p90) coupled with the S-100-related protein, p11. Annexin II has been suggested to be involved in exocytosis as it can restore the secretory responsiveness of permeabilized chromaffin cells. By quantitative confocal immunofluorescence, immunoreplica analysis and immunoprecipitation, we show here the translocation of p36 from the cytosol to a subplasmalemmal Triton X-100 insoluble fraction in chromaffin cells following nicotinic stimulation. A synthetic peptide corresponding to the NH2-terminal domain of p36 which contains the phosphorylation sites was microinjected into individual chromaffin cells and catecholamine secretion was monitored by amperometry. This peptide blocked completely the nicotine-induced recruitment of p36 to the cell periphery and strongly inhibited exocytosis evoked by either nicotine or high K+. The light chain of annexin II, p11, was selectively expressed by adrenergic chromaffin cells, and was only present in the subplasmalemmal Triton X-100 insoluble protein fraction of both resting and stimulated cells. p11 can modify the Ca(2+)- and/or the phospholipid-binding properties of p36. We found that loss Ca2+ was required to stimulate the translocation of p36 and to trigger exocytosis in adrenergic chromaffin cells. Our findings suggest that the translocation of p36 to the subplasmalemmal region is an essential event in regulated exocytosis and support the idea that the presence of p11 in adrenergic cells may confer a higher Ca2+ affinity to the exocytotic pathway in these cells.

scholarly journals Differential Intracellular Distributions of Inositol Trisphosphate and Ryanodine Receptors Within and Among Hematopoietic Cells

2005 ◽  
Vol 53 (7) ◽  
pp. 913-916 ◽  
Author(s):  
Andrea J. Clark ◽  
Howard R. Petty
Keyword(s):  
Ryanodine Receptor ◽  
Immunofluorescence Microscopy ◽  
Ryanodine Receptors ◽  
Hematopoietic Cells ◽  
Cell Integrity ◽  
Fixation Methods ◽  
Inositol 1,4,5 Trisphosphate ◽  
Intracellular Ca ◽  
A Cell ◽  
Trisphosphate Receptor

To better understand the mechanism(s) of leukocyte Ca2+ signaling, we have studied the intracellular locations of two Ca2+-mobilizing receptors, the inositol 1,4,5-trisphosphate receptor and ryanodine receptor, by immunofluorescence microscopy. Our results show that localization differs not only between receptor classes within a cell, but among leukocyte types as well. We also illustrate the importance of preserving labile cellular filaments in maintaining cell integrity by fixation with the Safiejko-Mroczka and Bell protocol, because conventional fixation methods distort receptor patterns. We suggest that the observed differences influence intracellular Ca2+ signaling.

Calcium signalling in early divergence of Metazoa: mechanisms involved in the control of muscle-like cell contraction in Hydra plagiodesmica

2019 ◽  
Vol 97 (9) ◽  
pp. 812-824 ◽  
Author(s):  
María Eugenia Alzugaray ◽  
María Victoria Gavazzi ◽  
Jorge Rafael Ronderos
Keyword(s):  
Endoplasmic Reticulum ◽  
Homo Sapiens ◽  
Ryanodine Receptors ◽  
Calcium Signalling ◽  
Cell Contraction ◽  
Inositol 1,4,5 Trisphosphate ◽  
Trisphosphate Receptor

Our laboratory has previously examined the effect of neuropeptides on the activity of the hypostome of the hydra Hydra plagiodesmica Dioni, 1968 (Cnidaria: Hydrozoa). These results showed that the hypostome, a structure extruded during feeding, responds to myoregulatory peptides and that this mechanism might be regulated by changes in the cytosolic levels of calcium (Ca2+). We analyse now the ways in which Ca2+ modulates hypostome activity during feeding. The use of calcium chelators confirms that Ca2+ is relevant in inducing hypostome extrusion. The assay of compounds that modulate the activity of Ca2+ channels in the endoplasmic reticulum suggests that, beyond the extracellular influx of calcium, intracellular sources of the ion are involved and might include both ryanodine receptors (RyR) and the inositol 1,4,5-trisphosphate receptor (IP3R). Bioinformatic searches based on sequences of RyR and IP3R of humans (Homo sapiens Linnaeus, 1758) show that IP3Rs are present in all groups analysed, including Fungi and Choanoflagellata. Although H. plagiodesmica responds to caffeine and ryanodine, which are known to modulate RyRs, this family of receptors seems not to be predicted in Cnidaria, suggesting that this phylum either lacks these kinds of channels or that they possess a different structure compared with those possessed by other Metazoa.

Sign in / Sign up

Export Citation Format

Share Document