Allergen-induced hyperresponsiveness to bradykinin is more pronounced than that to methacholine

1995 ◽  
Vol 78 (5) ◽  
pp. 1844-1852 ◽  
Author(s):  
A. R. Berman ◽  
A. G. Togias ◽  
G. Skloot ◽  
D. Proud
Keyword(s):  
Smooth Muscle ◽  
Vascular Permeability ◽  
Nerve Stimulation ◽  
Time Course ◽  
Sensory Nerve ◽  
Asthmatic Patients ◽  
Sensitive Index ◽  
Allergen Provocation ◽  
Allergen Inhalation ◽  
Induced Changes

Bradykinin reduces airflow in asthmatic patients via indirect mechanism(s), possibly involving sensory nerve stimulation and increased vascular permeability. We hypothesized that allergen inhalation, which affects reactivity of nerves and vessels, would differentially alter reactivity to bradykinin and the smooth muscle spasmogen methacholine. We compared reactivity to methacholine and bradykinin 1, 2, 4, 7, 11, and 14 days after allergen provocation in 12 atopic asthmatic patients with stable baseline reactivity to bradykinin. Maximal allergen-induced shifts from baseline in reactivity were 0.73 +/- 0.12 log unit for bradykinin compared with 0.27 +/- 0.13 log units for methacholine (P = 0.0005). Nine subjects showed significant increases in bradykinin reactivity, with four subjects increasing reactivity by > 1 log unit. Moreover, the maximal mean change in bradykinin reactivity occurred 2 days postallergen. Thus, allergen-induced changes in reactivity to bradykinin and methacholine differ in magnitude and time course. Bradykinin inhalational challenge provides a sensitive index of the airway's response to allergen.

scholarly journals Phospholemman does not participate in forskolin-induced swine carotid artery relaxation

2008 ◽  
pp. 669-676
Author(s):  
MK Meeks ◽  
S Han ◽  
AL Tucker ◽  
CM Rembold
Keyword(s):  
Smooth Muscle ◽  
Heat Shock ◽  
Carotid Artery ◽  
Dose Response ◽  
Time Course ◽  
Light Chains ◽  
Regulatory Light Chains ◽  
Heat Shock Protein 20 ◽  
Arterial Relaxation ◽  
Induced Changes

Phosphorylation of phospholemman (PLM) on ser68 has been proposed to at least partially mediate cyclic AMP (cAMP) mediated relaxation of arterial smooth muscle. We evaluated the time course of the phosphorylation of phospholemman (PLM) on ser68, myosin regulatory light chains (MRLC) on ser19, and heat shock protein 20 (HSP20) on ser16 during a transient forskolininduced relaxation of histamine-stimulated swine carotid artery. We also evaluated the dose response for forskolin- and nitroglycerin-induced relaxation in phenylephrine-stimulated PLM-/- and PLM+/+ mice. The time course for changes in ser19 MRLC dephosphorylation and ser16 HSP20 phosphorylation was appropriate to explain the forskolin-induced relaxation and the recontraction observed upon washout of forskolin. However, the time course for changes in ser68 PLM phosphorylation was too slow to explain forskolin-induced changes in force. There was no difference in the phenylephrine contractile dose response or in forskolin-induced relaxation dose response observed in PLM-/- and PLM+/+ aortae. In aortae precontracted with phenylephrine, nitroglycerin induced a slightly, but significantly greater relaxation in PLM-/- compared to PLM+/+ aortae. These data are consistent with the hypothesis that ser19 MRLC dephosphorylation and ser16 HSP20 phosphorylation are involved in forskolininduced relaxation. Our data suggest that PLM phosphorylation is not significantly involved in forskolin-induced arterial relaxation.

scholarly journals Use of transcranial magnetic stimulation to assess relaxation rates in unfatigued and fatigued knee-extensor muscles

2020 ◽  
Author(s):  
Gianluca Vernillo ◽  
Arash Khassetarash ◽  
Guillaume Y. Millet ◽  
John Temesi
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Relaxation Rate ◽  
Nerve Stimulation ◽  
Magnetic Stimulation ◽  
Time Course ◽  
Muscle Relaxation ◽  
Femoral Nerve ◽  
Relaxation Rates ◽  
Repeatability Coefficient ◽  
Induced Changes

Abstract We examined whether transcranial magnetic stimulation (TMS) delivered to the motor cortex allows assessment of muscle relaxation rates in unfatigued and fatigued knee extensors (KE). We assessed the ability of this technique to measure time course of fatigue-induced changes in muscle relaxation rate and compared relaxation rate from resting twitches evoked by femoral nerve stimulation. Twelve healthy men performed maximal voluntary isometric contractions (MVC) twice before (PRE) and once at the end of a 2-min KE MVC and five more times within 8 min during recovery. Relative (intraclass correlation coefficient; ICC2,1) and absolute (repeatability coefficient) reliability and variability (coefficient of variation) were assessed. Time course of fatigue-induced changes in muscle relaxation rate was tested with generalized estimating equations. In unfatigued KE, peak relaxation rate coefficient of variation and repeatability coefficient were similar for both techniques. Mean (95% CI) ICC2,1 for peak relaxation rates were 0.933 (0.724–0.982) and 0.889 (0.603–0.968) for TMS and femoral nerve stimulation, respectively. TMS-induced normalized muscle relaxation rate was − 11.5 ± 2.5 s−1 at PRE, decreased to − 6.9 ± 1.2 s−1 (− 37 ± 17%, P < 0.001), and recovered by 2 min post-exercise. Normalized peak relaxation rate for resting twitch did not show a fatigue-induced change. During fatiguing KE exercise, the change in muscle relaxation rate as determined by the two techniques was different. TMS provides reliable values of muscle relaxation rates. Furthermore, it is sufficiently sensitive and more appropriate than the resting twitch evoked by femoral nerve stimulation to reveal fatigue-induced changes in KE.

scholarly journals Time-Course Analysis on the Differentiation of Bone Marrow-Derived Progenitor Cells Into Smooth Muscle Cells During Neointima Formation

2010 ◽  
Vol 30 (10) ◽  
pp. 1890-1896 ◽  
Author(s):  
Jan-Marcus Daniel ◽  
Wiebke Bielenberg ◽  
Philipp Stieger ◽  
Soenke Weinert ◽  
Harald Tillmanns ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Progenitor Cells ◽  
Time Course ◽  
Muscle Cells ◽  
Neointima Formation

scholarly journals Chronic Stress-Induced Changes in Pro-Inflammatory Cytokines and Spinal Glia Markers in the Rat: A Time Course Study

2012 ◽  
Vol 19 (6) ◽  
pp. 367-376 ◽  
Author(s):  
Viktoriya Golovatscka ◽  
Helena Ennes ◽  
Emeran A. Mayer ◽  
Sylvie Bradesi
Keyword(s):  
Chronic Stress ◽  
Inflammatory Cytokines ◽  
Time Course ◽  
Time Course Study ◽  
Induced Changes ◽  
Pro Inflammatory Cytokines

scholarly journals Complementary vasoactivity and matrix remodelling in arterial adaptations to altered flow and pressure

2008 ◽  
Vol 6 (32) ◽  
pp. 293-306 ◽  
Author(s):  
A Valentín ◽  
L Cardamone ◽  
S Baek ◽  
J.D Humphrey
Keyword(s):  
Smooth Muscle ◽  
Continuum Theory ◽  
Muscle Contractility ◽  
Smooth Muscle Contractility ◽  
Rates Of Change ◽  
Biomechanical Loading ◽  
Smooth Muscle Proliferation ◽  
And Function ◽  
Diverse Data ◽  
Induced Changes

Arteries exhibit a remarkable ability to adapt to sustained alterations in biomechanical loading, probably via mechanisms that are similarly involved in many arterial pathologies and responses to treatment. Of particular note, diverse data suggest that cell and matrix turnover within vasoaltered states enables arteries to adapt to sustained changes in blood flow and pressure. The goal herein is to show explicitly how altered smooth muscle contractility and matrix growth and remodelling work together to adapt the geometry, structure, stiffness and function of a representative basilar artery. Towards this end, we employ a continuum theory of constrained mixtures to model evolving changes in the wall, which depend on both wall shear stress-induced changes in vasoactive molecules (which alter smooth muscle proliferation and synthesis of matrix) and intramural stress-induced changes in growth factors (which alter cell and matrix turnover). Simulations show, for example, that such considerations help explain the different rates of experimentally observed adaptations to increased versus decreased flows as well as differences in rates of change in response to increased flows or pressures.

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