Effect of halothane on intracellular calcium oscillations in porcine tracheal smooth muscle cells

1999 ◽  
Vol 276 (1) ◽  
pp. L81-L89 ◽  
Author(s):  
Christina M. Pabelick ◽  
Y. S. Prakash ◽  
Mathur S. Kannan ◽  
Keith A. Jones ◽  
David O. Warner ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Ryanodine Receptor ◽  
Muscle Cells ◽  
Calcium Oscillations ◽  
Tracheal Smooth Muscle ◽  
Permeabilized Cells ◽  
Inositol 1,4,5 Trisphosphate ◽  
Intracellular Ca ◽  
Trisphosphate Receptor

The effect of halothane on intracellular Ca2+ concentration ([Ca2+]i) regulation in porcine tracheal smooth muscle cells was examined with real-time confocal microscopy. Both 1 and 2 minimum alveolar concentration (MAC) halothane increased basal [Ca2+]iwhen Ca2+ influx and efflux were blocked, suggesting increased sarcoplasmic reticulum (SR) Ca2+ leak and/or decreased reuptake. In β-escin-permeabilized cells, heparin inhibition of inositol 1,4,5-trisphosphate-receptor channels blunted the halothane-induced increase in [Ca2+]i. Both 1 and 2 MAC halothane decreased the frequency and amplitude of ACh-induced [Ca2+]ioscillations (which represent SR Ca2+ release through ryanodine-receptor channels), abolishing oscillations in ∼20% of tracheal smooth muscle cells at 2 MAC. When Ca2+ influx and efflux were blocked, halothane increased the baseline and decreased the frequency and amplitude of [Ca2+]ioscillations, inhibiting oscillations in ∼70% of cells at 2 MAC. The fall time of [Ca2+]ioscillations and the rate of fall of the [Ca2+]iresponse to caffeine were both increased by halothane. These results suggest that halothane abolishes agonist-induced [Ca2+]ioscillations by 1) depleting SR Ca2+ via increased Ca2+ leak through inositol 1,4,5-trisphosphate-receptor channels, 2) decreasing Ca2+ release through ryanodine-receptor channels, and 3) inhibiting reuptake.

ATP stimulates Ca2+oscillations and contraction in airway smooth muscle cells of mouse lung slices

2002 ◽  
Vol 283 (6) ◽  
pp. L1271-L1279 ◽  
Author(s):  
Albrecht Bergner ◽  
Michael J. Sanderson
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Phospholipase C ◽  
Airway Smooth Muscle ◽  
Muscle Cells ◽  
Mouse Lung ◽  
Airway Smooth Muscle Cells ◽  
Airway Caliber ◽  
Inositol 1,4,5 Trisphosphate ◽  
Trisphosphate Receptor

In airway smooth muscle cells (SMCs) from mouse lung slices, ≥10 μM ATP induced Ca2+oscillations that were accompanied by airway contraction. After ∼1 min, the Ca2+oscillations subsided and the airway relaxed. By contrast, ≥0.5 μM adenosine 5′- O-(3-thiotriphosphate) (nonhydrolyzable) induced Ca2+oscillations in the SMCs and an associated airway contraction that persisted for >2 min. Adenosine 5′- O-(3-thiotriphosphate)-induced Ca2+oscillations occurred in the absence of external Ca2+but were abolished by the phospholipase C inhibitor U-73122 and the inositol 1,4,5-trisphosphate receptor inhibitor xestospongin. Adenosine, AMP, and α,β-methylene ATP had no effect on airway caliber, and the magnitude of the contractile response induced by a variety of nucleotides could be ranked in the following order: ATP = UTP > ADP. These results suggest that the SMC response to ATP is impaired by ATP hydrolysis and mediated via P2Y2or P2Y4receptors, activating phospholipase C to release Ca2+via the inositol 1,4,5-trisphosphate receptor. We conclude that ATP can serve as a spasmogen of airway SMCs and that Ca2+oscillations in SMCs are required to sustain airway contraction.

A1080 EFFECT OF HALOTHANE ON CALCIUM OSCILLATIONS IN PORCINE TRACHEAL SMOOTH MUSCLE CELLS

1997 ◽  
Vol 87 (Supplement) ◽  
pp. 1080A
Author(s):  
C.M. Pabelick ◽  
Y.S. Prakash ◽  
&NA; Kannan ◽  
K.A. Jones ◽  
&NA; Warner ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Muscle Cells ◽  
Calcium Oscillations ◽  
Tracheal Smooth Muscle

Thapsigargin stimulates Ca2+ entry in vascular smooth muscle cells: nicardipine-sensitive and -insensitive pathways

1992 ◽  
Vol 262 (5) ◽  
pp. C1258-C1265 ◽  
Author(s):  
Y. T. Xuan ◽  
O. L. Wang ◽  
A. R. Whorton
Keyword(s):  
Smooth Muscle ◽  
Sarcoplasmic Reticulum ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Vascular Smooth Muscle Cells ◽  
Muscle Cells ◽  
Inositol Polyphosphate ◽  
Inositol Polyphosphates ◽  
Permeabilized Cells ◽  
Inositol 1,4,5 Trisphosphate

We have investigated the role of the sarcoplasmic reticulum Ca2+ pool in regulating Ca2+ entry in vascular smooth muscle cells using a receptor-independent means of mobilizing the intracellular Ca2+ pool. Thapsigargin (TG) has been shown to inhibit the endoplasmic reticulum Ca(2+)-ATPase, mobilize intracellular Ca2+, and activate Ca2+ entry in nonmuscle tissues. When smooth muscle cells were treated with 0.2 microM TG, cytosolic Ca2+ concentrations rose gradually over 8 min to a peak value of 365 +/- 18 nM. Cytosolic Ca2+ remained elevated for at least 20 min and was supported by continued entry of extracellular Ca2+. TG also stimulated entry of Mn2+ and 45Ca2+ from outside the cell. Importantly, TG-induced Ca2+ entry and Mn2+ entry were found to occur through mechanisms that were independent of L-type Ca2+ channel activation because influx was not inhibited by concentrations of nicardipine that were found to block either endothelin- or 100 mM extracellular K(+)-induced cation influx. The mechanism through which TG activates cation entry appears to involve mobilization of the inositol 1,4,5-trisphosphate-responsive intracellular Ca2+ pool. In permeabilized cells, TG prevented ATP-stimulated Ca2+ uptake into the sarcoplasmic reticulum and slowly released sequestered Ca2+. The Ca2+ pool involved was responsive to inositol 1,4,5-trisphosphate. However, TG did not initiate the formation of inositol polyphosphates. Thus TG mobilizes the sarcoplasmic reticulum Ca2+ pool and activates Ca2+ entry through a nicardipine-insensitive Ca2+ channel in vascular smooth muscle. The mechanism is independent of inositol polyphosphate formation.

scholarly journals Type 1 inositol 1,4,5-trisphosphate receptors mediate UTP-induced cation currents, Ca2+ signals, and vasoconstriction in cerebral arteries

2008 ◽  
Vol 295 (5) ◽  
pp. C1376-C1384 ◽  
Author(s):  
Guiling Zhao ◽  
Adebowale Adebiyi ◽  
Eva Blaskova ◽  
Qi Xi ◽  
Jonathan H. Jaggar
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Cerebral Artery ◽  
Purinergic Receptor ◽  
Cerebral Arteries ◽  
Muscle Cells ◽  
Physiological Functions ◽  
Inositol 1,4,5 Trisphosphate ◽  
Intracellular Ca

Inositol 1,4,5-trisphosphate receptors (IP3Rs) regulate diverse physiological functions, including contraction and proliferation. There are three IP3R isoforms, but their functional significance in arterial smooth muscle cells is unclear. Here, we investigated relative expression and physiological functions of IP3R isoforms in cerebral artery smooth muscle cells. We show that 2-aminoethoxydiphenyl borate and xestospongin C, membrane-permeant IP3R blockers, reduced Ca2+ wave activation and global intracellular Ca2+ ([Ca2+]i) elevation stimulated by UTP, a phospholipase C-coupled purinergic receptor agonist. Quantitative PCR, Western blotting, and immunofluorescence indicated that all three IP3R isoforms were expressed in acutely isolated cerebral artery smooth muscle cells, with IP3R1 being the most abundant isoform at 82% of total IP3R message. IP3R1 knockdown with short hairpin RNA (shRNA) did not alter baseline Ca2+ wave frequency and global [Ca2+]i but abolished UTP-induced Ca2+ wave activation and reduced the UTP-induced global [Ca2+]i elevation by ∼61%. Antibodies targeting IP3R1 and IP3R1 knockdown reduced UTP-induced nonselective cation current ( Icat) activation. IP3R1 knockdown also reduced UTP-induced vasoconstriction in pressurized arteries with both intact and depleted sarcoplasmic reticulum (SR) Ca2+ by ∼45%. These data indicate that IP3R1 is the predominant IP3R isoform expressed in rat cerebral artery smooth muscle cells. IP3R1 stimulation contributes to UTP-induced Icat activation, Ca2+ wave generation, global [Ca2+]i elevation, and vasoconstriction. In addition, IP3R1 activation constricts cerebral arteries in the absence of SR Ca2+ release by stimulating plasma membrane Icat.

scholarly journals Ca2+ release from the sarcoplasmic reticulum is required for sustained TRPM4 activity in cerebral artery smooth muscle cells

2010 ◽  
Vol 299 (2) ◽  
pp. C279-C288 ◽  
Author(s):  
Albert L. Gonzales ◽  
Gregory C. Amberg ◽  
Scott Earley
Keyword(s):  
Smooth Muscle ◽  
Sarcoplasmic Reticulum ◽  
Patch Clamp ◽  
Smooth Muscle Cells ◽  
Cerebral Artery ◽  
Perforated Patch ◽  
Inositol 1,4,5 Trisphosphate ◽  
Intracellular Ca ◽  
Trisphosphate Receptor ◽  
Perforated Patch Clamp

The melastatin transient receptor potential (TRP) channel TRPM4 is a critical regulator of vascular smooth muscle cell membrane potential and contractility. Activation of the channel is Ca2+-dependent, but prolonged exposure to high (>1 μM) levels of intracellular Ca2+ causes rapid (within ∼2 min) desensitization of TRPM4 currents under conventional whole cell and inside-out patch-clamp conditions. The goal of the present study was to establish a novel method to record sustained TRPM4 currents in smooth muscle cells under near-physiological conditions. Using the amphotericin B-perforated patch-clamp technique, we recorded and characterized sustained (up to 30 min) transient inward cation currents (TICCs) in freshly isolated cerebral artery myocytes. In symmetrical cation solutions, TICCs reversed at 0 mV and had an apparent unitary conductance of 25 pS. Replacement of extracellular Na+ with the nonpermeable cation N-methyl-d-glucamine abolished the current. TICC activity was attenuated by the TRPM4 blockers fluflenamic acid and 9-phenanthrol. Selective silencing of TRPM4 expression using small interfering RNA diminished TICC activity, suggesting that the molecular identity of the responsible ion channel is TRPM4. We used the perforated patch-clamp method to test the hypothesis that TRPM4 is activated by intracellular Ca2+ signaling events. We found that TICC activity is independent of Ca2+ influx and ryanodine receptor activity but is attenuated by sarco(endo)plasmic reticulum Ca2+-ATPase inhibition and blockade of inositol 1,4,5-trisphosphate receptor-mediated Ca2+ release from the sarcoplasmic reticulum. Our findings suggest that TRPM4 channels in cerebral artery myocytes are regulated by Ca2+ release from inositol 1,4,5-trisphosphate receptor on the sarcoplasmic reticulum.

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