Prostaglandin modulation of adrenergic vascular control during hemorrhagic shock

This study was designed to evaluate 1) whether the initial compensatory skeletal muscle vascular constriction induced by hemorrhagic hypotension is primarily the result of increased adrenergic neural tone rather than circulating vasoconstrictor agents, and 2) whether the secondary skeletal muscle decompensatory vasodilation is caused by inhibitory action of prostaglandins on peripheral adrenergic nervous system. A constant-flow vascularly isolated double canine gracilis muscle preparation in which one muscle served as innervated control for the contralateral muscle was used. Dogs were subjected to standard stepwise hemorrhagic shock protocol. In series 1, perfusion pressures of control muscles were compared to denervated muscles with the result that innervated muscle perfusion pressures increased initially from 105 to 175 mmHg but subsequently fell significantly (P less than 0.05) to 147 mmHg. Only modest increases in perfusion pressures with no significant secondary fall were noted in denervated muscles. Series 2 compared innervated control perfusion pressures to pressures perfusing muscles pretreated with prostaglandin-synthesis inhibitor sodium meclofenamate (MCF). The MCF-treated muscle perfusion pressures rose to 260 mmHg where they remained without the secondary fall noted in control muscles. These data support the two hypotheses tested.

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Prostaglandins mediate skeletal muscle arteriole dilation in hyperdynamic bacteremia

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1990.259.3.h728 ◽

1990 ◽

Vol 259 (3) ◽

pp. H728-H734

Author(s):

H. G. Cryer ◽

R. N. Garrison ◽

P. D. Harris ◽

B. H. Greenwald ◽

N. L. Alsip

Keyword(s):

Skeletal Muscle ◽

Topical Application ◽

Serotonin Receptors ◽

Cremaster Muscle ◽

Synthesis Inhibitor ◽

E Coli ◽

Decerebrate Rat ◽

Prostaglandin Synthesis Inhibitor ◽

Baseline Values

Live Escherichia coli bacteremia during the high cardiac output (hyperdynamic) phase of sepsis causes constriction of large arterioles but dilation of small arterioles in skeletal muscle. This study examines the role of dilator prostaglandins, serotonin, and histamine in these differential microvascular responses in the decerebrate rat that avoids the effects of drug anesthesia. Topical application of meclofenamate, a prostaglandin synthesis inhibitor, to the cremaster muscle 60 min after induction of E. coli bacteremia enhanced the constriction of large arterioles from 20 +/- 8 to 46 +/- 9% less than baseline and blunted the dilation of small arterioles from 39 +/- 9 to 17 +/- 7% above baseline values in the cremaster microcirculation. Induction of E. coli bacteremia after pretreatment of the cremaster with meclofenamate constricted large arterioles to 40 +/- 4% less than baseline and small arterioles to 31 +/- 4% less than baseline. This indicates that prostaglandins initiate small arteriole dilation in response to E. coli, but some other dilator factor is activated by prostaglandins to maintain small arteriole dilation during E. coli bacteremia. Topical application of cyproheptadine, an antagonist of both histamine and serotonin receptors, to the cremaster muscle did not alter the E. coli-induced constriction of large arterioles or the dilation of small arterioles in the cremaster microcirculation.

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Effect of rhythmic tetanic skeletal muscle contractions on peak muscle perfusion

Journal of Applied Physiology ◽

10.1152/japplphysiol.00339.2002 ◽

2003 ◽

Vol 94 (1) ◽

pp. 11-19 ◽

Cited By ~ 20

Author(s):

John L. Dobson ◽

L. Bruce Gladden

Keyword(s):

Skeletal Muscle ◽

Blood Flow ◽

Popliteal Artery ◽

Muscle Blood Flow ◽

Venous Pressure ◽

Mechanical Action ◽

Muscle Contractions ◽

Primary Role ◽

Muscle Perfusion ◽

In Series

The purpose of this investigation was to examine the effect of rhythmic tetanic skeletal muscle contractions on peak muscle perfusion by using spontaneously perfused canine gastrocnemii in situ. Simultaneous pulsatile blood pressures were measured by means of transducers placed in the popliteal artery and vein, and pulsatile flow was measured with a flow-through-type transit-time ultrasound probe placed in the venous return line. Two series of experiments were performed. In series 1, maximal vasodilation of the muscles' vascular beds was elicited by infusing a normal saline solution containing adenosine (29.3 mg/min) and sodium nitroprusside (180 μg/min) for 15 s and then simultaneously occluding both the popliteal artery and vein for 5 min. The release of occlusion initiated a maximal hyperemic response, during which time four tetanic contractions were induced with supramaximal voltage (6–8 V, 0.2-ms stimuli for 200-ms duration at 50 Hz, 1/s). In series 2, the muscles were stimulated for 3 min before the muscle contractions were stopped for a period of 3 s; stimulation was then resumed. The results of series 1 indicate that, although contractions lowered venous pressure, muscle blood flow was significantly reduced from 2,056 ± 246 to 1,738 ± 225 ml · kg−1 · min−1when contractions were initiated and then increased significantly to 1,925 ± 225 ml · kg−1 · min−1during the first 5 s after contractions were stopped. In series 2, blood flow after 3 min of contractions averaged 1,454 ± 149 ml · kg−1 · min−1. Stopping the contractions for 3 s caused blood flow to increase significantly to 1,874 ± 172 ml · kg−1 · min−1; blood flow declined significantly to 1,458 ± 139 ml · kg−1 · min−1when contractions were resumed. We conclude that the mechanical action of rhythmic, synchronous, maximal isometric tetanic skeletal muscle contractions inhibits peak muscle perfusion during maximal and near-maximal vasodilation of the muscle's vascular bed. This argues against a primary role for the muscle pump in achieving peak skeletal muscle blood flow.

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Effect of External Calcium and other Divalent Cations on K+ Contractures in Denervated Slow Skeletal Muscle Fibers of the Frog

Journal of Biomedical and Allied Research ◽

10.37191/mapsci-2582-4937-1(2)-009 ◽

2019 ◽

Author(s):

Leonardo Hernández

Keyword(s):

Skeletal Muscle ◽

Binding Capacity ◽

Divalent Cations ◽

Muscle Fibers ◽

Free Calcium ◽

Slow Skeletal Muscle ◽

Skeletal Muscle Fibers ◽

Free Calcium Concentration ◽

Chronic Denervation ◽

Denervated Muscles

The influence of Ca2+ and other divalent cations on contractile responses of slow skeletal muscle fibers of the frog (Rana pipiens) under conditions of chronic denervation was investigated.Isometric tension was recorded from slow bundles of normal and denervated cruralis muscle in normal solution and in solutions with free calcium concentration solution or in solutions where other divalent cations (Sr2+, Ni2+, Co2+ or Mn2+) substituted for calcium. In the second week after nerve section, in Ca2+-free solutions, we observed that contractures (evoked from 40 to 80 mM-K+) of non-denervated muscles showed significantly higher tensions (p<0.05), than those from denervated bundles. Likewise, in solutions where calcium was substituted by all divalent cations tested, with exception of Mn2+, the denervated bundles displayed lower tension than non-denervated, also in the second week of denervation. In this case, the Ca2+ substitution by Sr2+ caused the higher decrease in tension, followed by Co2+ and Ni2+, which were different to non-denervated bundles, as the lowest tension was developed by Mn2+, followed by Co2+, and then Ni2+ and Sr2+. After the third week, we observed a recovery in tension. These results suggest that denervation altering the binding capacity to divalent cations of the voltage sensor.

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Ceramide down‐regulates System A amino acid transport and protein synthesis in rat skeletal muscle cells

The FASEB Journal ◽

10.1096/fj.04-2284fje ◽

2004 ◽

Vol 19 (3) ◽

pp. 1-24 ◽

Cited By ~ 71

Author(s):

Russell Hyde ◽

Eric Hajduch ◽

Darren J. Powell ◽

Peter M. Taylor ◽

Harinder S. Hundal

Keyword(s):

Skeletal Muscle ◽

Protein Synthesis ◽

Amino Acid ◽

Amino Acid Transport ◽

Muscle Cells ◽

Skeletal Muscle Cells ◽

Acid Transport ◽

Rat Skeletal Muscle ◽

System A

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Poly Silk Peptide Film PH Sensor Based on Zero Current Potentiometry

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.450-451.554 ◽

2012 ◽

Vol 450-451 ◽

pp. 554-556

Author(s):

Ming Ming Ma ◽

Zhi Tong ◽

Yong Wen

Keyword(s):

Graphite Electrode ◽

Ph Sensor ◽

Reference Electrode ◽

Pencil Graphite Electrode ◽

Solution Ph ◽

Counter Electrodes ◽

System A ◽

Zero Current ◽

In Series ◽

Silk Peptide

A poly silk peptide film pH sensor has been developed using zero current potentiometry system. A poly silk peptide film coated pencil graphite electrode is connected in series between the working and counter electrodes of a potentiostat, and immersed in solution together with a reference electrode. When the solution pH varies, the resulting zero current potentiometry is linear with the values of the solution pH in the range of 1.81 to 11.58. This pH sensor shows high stability, accuracy, selectivity and reproduction.

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Neural regulation of the formation of skeletal muscle phosphorylase kinase holoenzyme in adult and developing rat muscle

Biochemical Journal ◽

10.1042/bj3250793 ◽

1997 ◽

Vol 325 (3) ◽

pp. 793-800 ◽

Cited By ~ 2

Author(s):

Dean C. NG ◽

Richard C. CARLSEN ◽

Donal A. WALSH

Keyword(s):

Skeletal Muscle ◽

Muscle Development ◽

Rapid Decline ◽

Phosphorylase Kinase ◽

Β Subunit ◽

Subunit Protein ◽

Subunit Mrna ◽

Γ Subunit ◽

Muscle Phosphorylase ◽

Denervated Muscles

Neural influences on the co-ordination of expression of the multiple subunits of skeletal muscle phosphorylase kinase and their assembly to form the holoenzyme complex, α4β4γ4δ4, have been examined during denervation and re-innervation of adult skeletal muscle and during neonatal muscle development. Denervation of the tibialis anterior and extensor digitorum longus muscles of the rat hindlimb was associated with a rapid decline in the mRNA for the γ subunit, and an abrupt decrease in γ-subunit protein. The levels of the α- and β-subunit proteins in the denervated muscles also declined rapidly, their time course of reduction being similar to that for the γ-subunit protein, but they did not decrease to the same extent. In contrast with the rapid decline in γ-subunit mRNA upon denervation, α- and β-subunit mRNAs stayed at control innervated levels for approx. 8–10 days, but then decreased rapidly. Their decline coincided very closely with the onset of re-innervation. Re-innervation of the denervated muscles, which occurs rapidly and uniformly after the sciatic nerve crush injury, produced an eventual slow and prolonged recovery of the mRNA for all three subunits and parallel increases in each of the subunit proteins. A similar co-ordinated increase of both subunit mRNA and subunit proteins of the phosphorylase kinase holoenzyme was observed during neonatal muscle development, during the period when the muscles were attaining their adult pattern of motor activity. The phosphorylase kinase holoenzyme remains in a non-activated form during all of these physiological changes, as is compatible with the presence of the full complement of the regulatory subunits. These data are consistent with a model whereby the transcriptional and translational expression of phosphorylase kinase γ subunit occurs only with concomitant expression of the α and β subunits. This would ensure that free and unregulated, activated γ subunit alone, which would give rise to unregulated glycogenolysis, is not produced. The data also suggest that control of phosphorylase kinase subunit expression and the formation of the holoenzyme in skeletal muscle is provided by the motor nerve, probably through imposed levels or patterns of muscle activity.

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Effect of hemorrhagic shock, fasting, and corticosterone administration on leucine oxidation and incorporation into protein by skeletal muscle

Metabolism ◽

10.1016/0026-0495(74)90038-9 ◽

1974 ◽

Vol 23 (10) ◽

pp. 901-904 ◽

Cited By ~ 27

Author(s):

N.Thomas Ryan ◽

Barbara C. George ◽

Richard Odessey ◽

Richard H. Egdahl

Keyword(s):

Skeletal Muscle ◽

Hemorrhagic Shock ◽

Leucine Oxidation

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AMP kinase is not required for the GLUT4 response to exercise and denervation in skeletal muscle

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00080.2004 ◽

2004 ◽

Vol 287 (4) ◽

pp. E739-E743 ◽

Cited By ~ 46

Author(s):

Burton F. Holmes ◽

David B. Lang ◽

Morris J. Birnbaum ◽

James Mu ◽

G. Lynis Dohm

Keyword(s):

Skeletal Muscle ◽

Dominant Negative ◽

Treadmill Running ◽

Wild Type ◽

Α Subunit ◽

Ampk Activity ◽

Denervated Muscles ◽

Amp Activated Protein Kinase ◽

Response To Exercise

An acute bout of exercise increases muscle GLUT4 mRNA in mice, and denervation decreases GLUT4 mRNA. AMP-activated protein kinase (AMPK) activity in skeletal muscle is also increased by exercise, and GLUT4 mRNA is increased in mouse skeletal muscle after treatment with AMPK activator 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside(AICAR). These findings suggest that AMPK activation might be responsible for the increase in GLUT4 mRNA expression in response to exercise. To investigate the role of AMPK in GLUT4 regulation in response to exercise and denervation, transgenic mice with a mutated AMPK α-subunit (dominant negative; AMPK-DN) were studied. GLUT4 did not increase in AMPK-DN mice that were treated with AICAR, demonstrating that muscle AMPK is inactive. Exercise (two 3-h bouts of treadmill running separated by 1 h of rest) increased GLUT4 mRNA in both wild-type and AMPK-DN mice. Likewise, denervation decreased GLUT4 mRNA in both wild-type and AMPK-DN mice. GLUT4 mRNA was also increased by AICAR treatment in both the innervated and denervated muscles. These data demonstrate that AMPK is not required for the response of GLUT4 mRNA to exercise and denervation.

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