scholarly journals Role of α-adrenergic vasoconstriction in regulating skeletal muscle blood flow and vascular conductance during forearm exercise in ageing humans

2014 ◽  
Vol 592 (21) ◽  
pp. 4775-4788 ◽  
Author(s):  
Jennifer C. Richards ◽  
Gary J. Luckasen ◽  
Dennis G. Larson ◽  
Frank A. Dinenno
Keyword(s):  
Skeletal Muscle ◽  
Blood Flow ◽  
Muscle Blood Flow ◽  
Vascular Conductance ◽  
Skeletal Muscle Blood Flow ◽  
Forearm Exercise

Skeletal muscle blood flow and vascular conductance are enhanced in humans with high‐affinity hemoglobin during handgrip exercise in severe hypoxia

2020 ◽  
Vol 34 (S1) ◽  
pp. 1-1
Author(s):  
Chad C. Wiggins ◽  
Paolo B. Dominelli ◽  
Jonathon W. Senefeld ◽  
John R.A. Shepherd ◽  
Sarah E. Baker ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Blood Flow ◽  
Muscle Blood Flow ◽  
Severe Hypoxia ◽  
Handgrip Exercise ◽  
Vascular Conductance ◽  
Skeletal Muscle Blood Flow ◽  
High Affinity

Muscle blood flow responses to dynamic exercise in young obese humans

2010 ◽  
Vol 108 (2) ◽  
pp. 349-355 ◽  
Author(s):  
Jacqueline K Limberg ◽  
Michael D. De Vita ◽  
Gregory M. Blain ◽  
William G. Schrage
Keyword(s):  
Skeletal Muscle ◽  
Body Mass Index ◽  
Blood Flow ◽  
Perfusion Pressure ◽  
Muscle Blood Flow ◽  
Dynamic Exercise ◽  
Vascular Conductance ◽  
Leg Exercise ◽  
Obese Subjects ◽  
Forearm Exercise

Exercise is a common nonpharmacological way to combat obesity; however, no studies have systematically tested whether obese humans exhibit reduced skeletal muscle blood flow during dynamic exercise. We hypothesized that exercise-induced blood flow to skeletal muscle would be lower in young healthy obese subjects (body mass index of >30 kg/m2) compared with lean subjects (body mass index of <25 kg/m2). We measured blood flow (Doppler Ultrasound of the brachial and femoral arteries), blood pressure (auscultation, Finapress), and heart rate (ECG) during rest and two forms of single-limb, steady-state dynamic exercise: forearm exercise (20 contractions/min at 4, 8, and 12 kg) and leg exercise (40 kicks/min at 7 and 14 W). Forearm exercise increased forearm blood flow (FBF) similarly in both groups ( P > 0.05; obese subjects n = 9, lean subjects n = 9). When FBF was normalized for perfusion pressure, forearm vascular conductance was not different between groups at increasing workloads ( P > 0.05). Leg exercise increased leg blood flow (LBF) similarly in both groups ( P > 0.05; obese subjects n = 10, lean subjects n = 12). When LBF was normalized for perfusion pressure, leg vascular conductance was not different between groups at increasing workloads ( P > 0.05). These results were confirmed when relative blood flow was expressed at average relative workloads. In conclusion, our results show that obese subjects exhibited preserved FBF and LBF during dynamic exercise.

scholarly journals Exercise training improves blood flow to contracting skeletal muscle of older men via enhanced cGMP signaling

2018 ◽  
Vol 124 (1) ◽  
pp. 109-117 ◽  
Author(s):  
Peter Piil ◽  
Tue Smith Jørgensen ◽  
Jon Egelund ◽  
Rasmus Damsgaard ◽  
Lasse Gliemann ◽  
...  
Keyword(s):  
Physical Activity ◽  
Skeletal Muscle ◽  
Blood Flow ◽  
Exercise Training ◽  
Oxidative Metabolism ◽  
Muscle Blood Flow ◽  
Older Men ◽  
Skeletal Muscle Blood Flow ◽  
Cgmp Signaling

Physical activity has the potential to offset age-related impairments in the regulation of blood flow and O2 delivery to the exercising muscles; however, the mechanisms underlying this effect of physical activity remain poorly understood. The present study examined the role of cGMP in training-induced adaptations in the regulation of skeletal muscle blood flow and oxidative metabolism during exercise in aging humans. We measured leg hemodynamics and oxidative metabolism during exercise engaging the knee extensor muscles in young [ n = 15, 25 ± 1 (SE) yr] and older ( n = 15, 72 ± 1 yr) subjects before and after a period of aerobic high-intensity exercise training. To determine the role of cGMP signaling, pharmacological inhibition of phosphodiesterase 5 (PDE5) was performed. Before training, inhibition of PDE5 increased ( P < 0.05) skeletal muscle blood flow and O2 uptake during moderate-intensity exercise in the older group; however, these effects of PDE5 inhibition were not detected after training. These findings suggest a role for enhanced cGMP signaling in the training-induced improvement of regulation of blood flow in contracting skeletal muscle of older men. NEW & NOTEWORTHY The present study provides evidence for enhanced cyclic GMP signaling playing an essential role in the improved regulation of blood flow in contracting skeletal muscle of older men with aerobic exercise training.

scholarly journals Is tonic sympathetic vasoconstriction increased in the skeletal muscle vasculature of aged canines?

2010 ◽  
Vol 299 (5) ◽  
pp. R1342-R1349 ◽  
Author(s):  
D. S. DeLorey ◽  
J. B. Buckwalter ◽  
S. W. Mittelstadt ◽  
M. M. Anton ◽  
H. A. Kluess ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Blood Flow ◽  
Pyridoxal Phosphate ◽  
Muscle Blood Flow ◽  
Treadmill Running ◽  
Disulfonic Acid ◽  
Vascular Conductance ◽  
Skeletal Muscle Blood Flow ◽  
Npy Receptor ◽  
Sympathetic Vasoconstriction

We tested the hypothesis that tonic adrenergic and nonadrenergic receptor-mediated sympathetic vasoconstriction would increase at rest and during exercise with advancing age. Young ( n = 6; 22 ± 1 mo; means ± SE) and old ( n = 6; 118 ± 9 mo) beagles were studied. Selective antagonists for alpha-1, alpha-2, neuropeptide Y (NPY), and purinergic (P2x) receptors were infused at rest and during treadmill running at 2.5 mph and 4 mph with 2.5% grade. Prazosin produced similar increases in vascular conductance in young and old beagles at rest (Young: 158 ± 34%; Old: 98 ± 19%) and during exercise at 2.5 mph (Young: 80 ± 10%; Old: 58 ± 12%) and 4 mph and 2.5% grade (Young: 57 ± 5%; Old: 26 ± 4%). Rauwolscine caused similar ( P > 0.05) increases in vascular conductance in old compared with young dogs at rest (Young: 119 ± 25%; Old: 64 ± 22%) and at 2.5 mph (Young: 86 ± 13%; Old: 60 ± 7%) and 4 mph with 2.5% grade (Young: 61 ± 5%; Old: 43 ± 7%). N2-(diphenylacetyl)-N-[4-hydroxyphenyl)methyl]-d-arginine amide (BIBP) caused a smaller increase ( P < 0.05) in vascular conductance in old compared with young dogs at rest (Young: 179 ± 44%; Old: 91 ± 22%), whereas similar increases ( P > 0.05) of experimental limb vascular conductance in young and old dogs occurred following BIBP during exercise at 2.5 mph (Young: 56 ± 16%; Old: 50 ± 12%) and 4 mph and 2.5% grade (Young: 45 ± 10%; Old: 25 ± 7%). Pyridoxal-phosphate-6-azophenyl-2′-4′-disulfonic acid infusion produced a larger increase in vascular conductance in old compared with young beagles at rest (Young: 88 ± 14%; Old: 191 ± 58%), whereas similar increases were observed at 2.5 mph (Young: 47 ± 18%; Old: 31 ± 11%) and 4 mph with 2.5% grade (Young: 26 ± 13%; Old: −18 ± 8%). At rest, NPY receptor-mediated restraint of skeletal muscle blood flow was reduced with advancing age, whereas P2x receptor-mediated restraint of skeletal muscle blood flow was increased. During exercise, the magnitude of adrenergic and nonadrenergic sympathetic vasoconstriction was not different between young and old dogs. Overall, these data demonstrate that adrenergic receptor-mediated vasoconstriction was not elevated at rest, but nonadrenergic sympathetic vasoconstriction was altered under basal conditions in aged beagles.

Role of nitric oxide in skeletal muscle blood flow at rest and during dynamic exercise in humans

1997 ◽  
Vol 273 (1) ◽  
pp. H405-H410 ◽  
Author(s):  
R. C. Hickner ◽  
J. S. Fisher ◽  
A. A. Ehsani ◽  
W. M. Kohrt
Keyword(s):  
Nitric Oxide ◽  
Skeletal Muscle ◽  
Blood Flow ◽  
Vastus Lateralis ◽  
Muscle Blood Flow ◽  
Dynamic Exercise ◽  
Skeletal Muscle Blood Flow ◽  
Blood Flows ◽  
And Control

The role of nitric oxide at rest and in the active hyperemic response within skeletal muscle was investigated in eight physically active men. Three microdialysis probes were inserted into the vastus lateralis of the quadriceps femoris muscle group in each subject. Microdialysis probes were perfused with a Ringer solution containing 5.0 mM ethanol, 2.5 mM glucose, and either 10 mg/ml of the nitric oxide synthase inhibitor NG-monomethyl-L-arginine (L-NMMA) monoacetate salt, 30 mg/ml of the nitric oxide precursor L-arginine, or no additional substance (control probe). Subjects performed one-legged cycling exercise at work rates ranging from 25 to 100 W. Dialysate and perfusate ethanol concentrations were presented as the ratio of [ethanol]dialysate to [ethanol]perfusate (ethanol outflow-to-inflow ratio), an indicator that is inversely related to blood flow. The ethanol outflow-to-inflow ratios at rest were 0.614 +/- 0.032, 0.523 +/- 0.023, and 0.578 +/- 0.039 in the L-NMMA, L-arginine, and control probes, respectively. Calculated resting blood flows were therefore 8.7 +/- 4.1, 20.5 +/- 4.6, and 14.0 +/- 4.7 ml.min-1.100 g-1 around the L-NMMA, L-arginine, and control probes, respectively. The ethanol outflow-to-inflow ratios were significantly higher at all exercise intensities in the L-NMMA probe than in the control and L-arginine probes, resulting in calculated blood flows of 195 +/- 55, 407 +/- 47, and 352 +/- 60 ml.min-1.100 g-1 at 25 W and 268 +/- 65, 602 +/- 129, and 519 +/- 113 ml.min-1.100 g-1 at 100 W around the L-NMMA, L-arginine, and control probes, respectively. Skeletal muscle blood flow was therefore reduced both at rest and during continuous, dynamic exercise by the action of L-NMMA, whereas blood flow was increased only at rest by L-arginine.

Skeletal Muscle Blood Flow During Limb Movement: The Role Of Joint Angle.

2009 ◽  
Vol 41 ◽  
pp. 8
Author(s):  
Stephen J. Ives ◽  
John McDaniel ◽  
Anette S. Fjeldstad ◽  
Melissa A. Hayman ◽  
David W. Wray ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Blood Flow ◽  
Joint Angle ◽  
Muscle Blood Flow ◽  
Limb Movement ◽  
Skeletal Muscle Blood Flow

scholarly journals Role of Alpha‐1 Adrenergic Vasoconstriction in Regulating Skeletal Muscle Blood Flow during Single Leg Knee Extension Exercise with Advancing Age

2018 ◽  
Vol 32 (S1) ◽  
Author(s):  
Jeremy L. Theisen ◽  
Stephen M. Ratchford ◽  
Heather L. Clifton ◽  
Kanokwan Bunsawat ◽  
Zachary Barret‐O'keefe ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Blood Flow ◽  
Muscle Blood Flow ◽  
Knee Extension ◽  
Skeletal Muscle Blood Flow ◽  
Knee Extension Exercise
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