scholarly journals Caveolae from canine airway smooth muscle contain the necessary components for a role in Ca2+ handling

2000 ◽  
Vol 279 (6) ◽  
pp. L1226-L1235 ◽  
Author(s):  
Peter J. Darby ◽  
C. Y. Kwan ◽  
Edwin E. Daniel
Keyword(s):  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
Connexin 43 ◽  
Tracheal Smooth Muscle ◽  
Specific Marker ◽  
Cell Periphery ◽  
Caveolin 1 ◽  
Cytoplasmic Face ◽  
Detergent Treatment ◽  
Trisphosphate Receptor

To explain that bronchial smooth muscle undergoes sustained agonist-induced contractions in a Ca2+-free medium, we hypothesized that caveolae in the plasma membrane (PM) contain protected Ca2+. We isolated caveolae from canine tracheal smooth muscle by detergent treatment of PM-derived microsomes. Detergent-resistant membranes were enriched in caveolin-1, a specific marker for caveolae as well as for L-type Ca2+ channels and Ca2+ binding proteins (calsequestrin and calreticulin) as determined by Western blotting. Also, the PM Ca2+ pump was present but not connexin 43 (a noncaveolae PM protein), the sarcoplasmic reticulum (SR) Ca2+ pump, or the type 1 inositol 1,4,5-trisphosphate receptor, supporting the idea that SR-derived membranes were not present. Antibodies to caveolin coimmunoprecipitated caveolin with calsequestrin or calreticulin. Thus some of the cellular calsequestrin and calreticulin associated with caveolin on the cytoplasmic face of each caveola. Immunohistochemistry of tracheal smooth muscle crysosections confirmed the localization of caveolin and the PM Ca2+ pump to the cell periphery, whereas the SR Ca2+ pump was located deeper in the cell. The presence of L-type Ca2+ channels, the PM Ca2+ pump, and the Ca2+ bindng proteins calsequestrin and calreticulin in caveolin-enriched membranes supports caveola involvement in airway smooth muscle Ca2+ handling.

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.

Expression of dihydropyridine resistance differs in porcine bronchial and tracheal smooth muscle

1994 ◽  
Vol 267 (2) ◽  
pp. L106-L112 ◽  
Author(s):  
T. L. Croxton ◽  
C. Fleming ◽  
C. A. Hirshman
Keyword(s):  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
Isometric Tension ◽  
Tracheal Smooth Muscle ◽  
Airway Smooth Muscle Cells ◽  
Channel Blockers ◽  
Response Curves ◽  
Voltage Dependent ◽  
Relaxation Responses ◽  
Ca2 Channels

Voltage-dependent and receptor-operated Ca2+ entry mechanisms have been demonstrated in airway smooth muscle, but their relative importance for maintenance of contraction is unknown. Blockade of voltage-dependent Ca2+ channels (VDC) has produced inconsistent relaxation. We postulated regional variations in Ca2+ handling by airway smooth muscle cells and compared the efficacy of dihydropyridine VDC blockers in tracheas and bronchi. Porcine tracheal smooth muscle strips and bronchial rings were mounted in tissue baths filled with physiological solutions and isometric tension was measured. Tissues were precontracted with carbachol or KCl, and relaxation dose-response curves to nifedipine, Mn2+, or Cd2+ were obtained. Relaxation responses to nifedipine were significantly different in carbachol-contracted tracheas and bronchi. Whereas carbachol-contracted tracheal muscle completely relaxed with 10(-6) M nifedipine, bronchial smooth muscle relaxed < 50%. In contrast, KCl-contracted bronchial muscle was completely relaxed by nifedipine. The nonspecific Ca2+ channel blockers Mn2+ and Cd2+ produced similar relaxation responses in each tissue. Thus VDC are the predominant mechanism for Ca2+ entry in porcine tracheal smooth muscle, but a dihydropyridine-insensitive pathway is functionally important in carbachol-contracted porcine bronchi. Regional variation may account for apparent inconsistencies between previous studies.

Changes in cytosolic cGMP and calcium in airway smooth muscle relaxed by 3-morpholinosydnonimine

1994 ◽  
Vol 266 (1) ◽  
pp. L9-L16 ◽  
Author(s):  
K. A. Jones ◽  
R. R. Lorenz ◽  
D. O. Warner ◽  
Z. S. Katusic ◽  
G. C. Sieck
Keyword(s):  
Methylene Blue ◽  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
Calcium Concentration ◽  
Cytosolic Calcium ◽  
Tracheal Smooth Muscle ◽  
Relative Importance ◽  
Cytosolic Calcium Concentration ◽  
Fura 2 ◽  
Cyclic Monophosphate

Nitrovasodilators relax airway smooth muscle by both guanosine 3',5'-cyclic monophosphate (cGMP)-dependent and cGMP-independent mechanisms and by mechanisms that reduce cytosolic calcium concentration ([Ca2+]i). This study was conducted to determine the relative importance of these mechanisms in relaxation of canine tracheal smooth muscle (CTSM) induced by 3-morpholinosydnonimine (SIN-1). We measured 1) the effect of SIN-1 on force, [cGMP]i, and [Ca2+]i, and 2) the ability of methylene blue (MB) to antagonize SIN-1-induced relaxation and cGMP accumulation. The ratio of fura 2 emission fluorescence intensities due to excitation at 340- and 380-nm wavelengths (F340/F380) was used as an index of [Ca2+]i. In strips contracted with 0.3 microM acetylcholine (ACh, n = 8) or 24 mM KCl (n = 8), SIN-1 (1-100 microM) caused a concentration-dependent decrease in force which was correlated with a concentration-dependent increase in [cGMP]i. MB (10 microM) proportionally attenuated both relaxation and cGMP accumulation. In fura 2-loaded strips contracted with 0.3 microM ACh (n = 7) or 30 mM KCl (n = 7), reductions in force induced by SIN-1 (1-100 microM) were accompanied by decreases in F340/F380. These findings suggest that in CTSM contracted with ACh or KCl, SIN-1 causes relaxation which appears to be mediated by cGMP-dependent mechanisms that reduce [Ca2+]i.

Role of cyclic ADP-ribose in the regulation of [Ca2+]i in porcine tracheal smooth muscle

1998 ◽  
Vol 274 (6) ◽  
pp. C1653-C1660 ◽  
Author(s):  
Y. S. Prakash ◽  
Mathur S. Kannan ◽  
Timothy F. Walseth ◽  
Gary C. Sieck
Keyword(s):  
Smooth Muscle ◽  
Second Messenger ◽  
Ruthenium Red ◽  
Tracheal Smooth Muscle ◽  
Cyclic Adp Ribose ◽  
Intracellular Ca ◽  
Subsequent Exposure ◽  
Trisphosphate Receptor ◽  
Dose Dependent Increase

The purpose of the present study was to determine whether cyclic ADP-ribose (cADPR) acts as a second messenger for Ca2+ release through ryanodine receptor (RyR) channels in tracheal smooth muscle (TSM). Freshly dissociated porcine TSM cells were permeabilized with β-escin, and real-time confocal microscopy was used to examine changes in intracellular Ca2+ concentration ([Ca2+]i). cADPR (10 nM–10 μM) induced a dose-dependent increase in [Ca2+]i, which was blocked by the cADPR receptor antagonist 8-amino-cADPR (20 μM) and by the RyR blockers ruthenium red (10 μM) and ryanodine (10 μM), but not by the inositol 1,4,5-trisphosphate receptor blocker heparin (0.5 mg/ml). During steady-state [Ca2+]ioscillations induced by acetylcholine (ACh), addition of 100 nM and 1 μM cADPR increased oscillation frequency and decreased peak-to-trough amplitude. ACh-induced [Ca2+]ioscillations were blocked by 8-amino-cADPR; however, 8-amino-cADPR did not block the [Ca2+]iresponse to a subsequent exposure to caffeine. These results indicate that cADPR acts as a second messenger for Ca2+ release through RyR channels in TSM cells and may be necessary for initiating ACh-induced [Ca2+]ioscillations.

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.

Interleukin-1β-induced airway hyperresponsiveness enhances substance P in intrinsic neurons of ferret airway

2002 ◽  
Vol 283 (5) ◽  
pp. L909-L917 ◽  
Author(s):  
Z.-X. Wu ◽  
B. E. Satterfield ◽  
J. S. Fedan ◽  
R. D. Dey
Keyword(s):  
Smooth Muscle ◽  
Substance P ◽  
Airway Smooth Muscle ◽  
Airway Hyperresponsiveness ◽  
Sensory Nerves ◽  
Tracheal Smooth Muscle ◽  
Fiber Density ◽  
Smooth Muscle Contractility ◽  
Neurokinin 1

Interleukin (IL)-1β causes airway inflammation, enhances airway smooth muscle responsiveness, and alters neurotransmitter expression in sensory, sympathetic, and myenteric neurons. This study examines the role of intrinsic airway neurons in airway hyperresponsiveness (AHR) induced by IL-1β. Ferrets were instilled intratracheally with IL-1β (0.3 μg/0.3 ml) or saline (0.3 ml) once daily for 5 days. Tracheal smooth muscle contractility in vitro and substance P (SP) expression in tracheal neurons were assessed. Tracheal smooth muscle reactivity to acetylcholine (ACh) and methacholine (MCh) and smooth muscle contractions to electric field stimulation (EFS) both increased after IL-1β. The IL-1β-induced AHR was maintained in tracheal segments cultured for 24 h, a procedure that depletes SP from sensory nerves while maintaining viability of intrinsic airway neurons. Pretreatment with CP-99994, an antagonist of neurokinin 1 receptor, attenuated the IL-1β-induced hyperreactivity to ACh and MCh and to EFS in cultured tracheal segments. SP-containing neurons in longitudinal trunk, SP innervation of superficial muscular plexus neurons, and SP nerve fiber density in tracheal smooth muscle all increased after treatment with IL-1β. These results show that IL-1β-enhanced cholinergic airway smooth muscle contractile responses are mediated by the actions of SP released from intrinsic airway neurons.

Response to acetylcholine and myosin content of isolated canine airways

1989 ◽  
Vol 67 (4) ◽  
pp. 1331-1335 ◽  
Author(s):  
C. E. Mapp ◽  
P. Chitano ◽  
N. De Marzo ◽  
P. Di Blasi ◽  
M. Saetta ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
Muscle Thickness ◽  
Smooth Muscle Myosin ◽  
Tracheal Smooth Muscle ◽  
Fifth Generation ◽  
Maximal Tension ◽  
Muscle Myosin ◽  
The Relationship ◽  
Trachea And Bronchi

Contractility of tracheal smooth muscle strips and spiral strips of fourth to fifth generation bronchi was studied in organ baths. The relationship among contractility, airway smooth muscle myosin, and smooth muscle thickness was also examined. The trachea was divided into three segments, each consisting of 12–14 rings. Smooth muscle strips from each of the three regions (top, middle, and bottom of the trachea) and from fourth to fifth generation bronchi were studied. Acetylcholine (ACh) sensitivity (-log EC50) was 8.1, 7.1, 7.9, and 6.1 for the top, middle, and bottom of the trachea and the bronchi, respectively. At P = 0.01, the EC50 ACh value of the top of the trachea differed from the EC50 value of the bronchi. Maximal tension (Tmax) generated in bronchi (3.2 g) was lower (P less than 0.01) than in the top (10.4 g), middle (7.1 g), and bottom of the trachea (5.1 g). Differences between trachea and bronchi disappeared when Tmax was corrected for smooth muscle myosin content. Thickness of smooth muscle in bronchi was less (P less than 0.01) than in the three regions of trachea. Tmax was significantly correlated with airway smooth muscle thickness (r = 0.56; P less than 0.05). These results suggest that in mongrel dogs sensitivity to ACh shows a gradient from the top of the trachea to the bronchi and that Tmax is greater in the trachea than in the bronchi and is significantly correlated with thickness of smooth muscle.

Nerve growth factor-enhanced airway responsiveness involves substance P in ferret intrinsic airway neurons

2006 ◽  
Vol 291 (1) ◽  
pp. L111-L118 ◽  
Author(s):  
Z.-X. Wu ◽  
R. D. Dey
Keyword(s):  
Smooth Muscle ◽  
Nerve Growth Factor ◽  
Growth Factor ◽  
Treatment Group ◽  
Substance P ◽  
Airway Smooth Muscle ◽  
Airway Responsiveness ◽  
Tracheal Smooth Muscle ◽  
Control Group ◽  
Nerve Growth

Nerve growth factor (NGF), a member of the neurotrophin family, enhances synthesis of neuropeptides in sensory and sympathetic neurons. The aim of this study was to examine the effect of NGF on airway responsiveness and determine whether these effects are mediated through synthesis and release of substance P (SP) from the intrinsic airway neurons. Ferrets were instilled intratracheally with NGF or saline. Tracheal smooth muscle contractility to methacholine and electrical field stimulation (EFS) was assessed in vitro. Contractions of isolated tracheal smooth muscle to EFS at 10 and 30 Hz were significantly increased in the NGF treatment group (10 Hz: 33.57 ± 2.44%; 30 Hz: 40.12 ± 2.78%) compared with the control group (10 Hz: 27.24 ± 2.14%; 30 Hz: 33.33 ± 2.31%). However, constrictive response to cholinergic agonist was not significantly altered between the NGF treatment group and the control group. The NGF-induced modulation of airway smooth muscle to EFS was maintained in tracheal segments cultured for 24 h, a procedure that causes a significant anatomic and functional loss of SP-containing sensory fibers while maintaining viability of intrinsic airway neurons. The number of SP-containing neurons in longitudinal trunk and superficial muscular plexus and SP nerve fiber density in tracheal smooth muscle all increased significantly in cultured trachea treated with NGF. Pretreatment with CP-99994, an antagonist of neurokinin 1 receptor, attenuated the NGF-induced increased contraction to EFS in cultured segments but had no effect in saline controls. These results show that the NGF-enhanced airway smooth muscle contractile responses to EFS are mediated by the actions of SP released from intrinsic airway neurons.

Sign in / Sign up

Export Citation Format

Share Document