Plasma catecholamines and their effect on blood lactate and muscle lactate output

1984 ◽  
Vol 57 (2) ◽  
pp. 321-325 ◽  
Author(s):  
W. N. Stainsby ◽  
C. Sumners ◽  
G. M. Andrew
Keyword(s):  
Venous Blood ◽  
Plasma Catecholamines ◽  
Muscle Group ◽  
O2 Uptake ◽  
Plantaris Muscle ◽  
Muscle Lactate ◽  
Blood Samples ◽  
Lactate Output ◽  
Before And After

This study was designed to test the hypothesis that epinephrine (E) and norepinephrine (NE) increase net muscle lactate output (L) of in situ gastrocnemius-plantaris muscle group during contractions. Plasma [E] and [NE] were measured before and after the surgical isolation of the muscle and at 10-min intervals during the 60-min experiments. Plasma [E] and [NE] were increased threefold by intravenous infusions of E (n = 3) or NE (n = 3) at a rate of 1.5 micrograms X kg body wt-1 X min-1. Arterial and muscle venous blood samples for O2 and lactate concentrations were also obtained. The infusions began at min 11 and repetitive isometric contractions (4 tw/s) began at min 31. The presurgery plasma [E] and [NE] averaged 0.34 and 0.52 ng/ml, respectively, and rose to 1.12 and 1.19 ng/ml 10 min after surgery. Arterial and venous lactate concentrations (CaL and CvL) increased continuously during E infusion but remained constant during NE infusion. Maximal L during the first 10 min of contractions was significantly increased compared with an identical earlier study without infusions. O2 uptake was not changed by the infusions. It is concluded that E causes CaL to rise and that both E and NE increase maximal net lactate output during contractions.

O2 uptake and developed tension during and after fatigue, curare block, and ischemia

1978 ◽  
Vol 45 (5) ◽  
pp. 751-755 ◽  
Author(s):  
L. B. Gladden ◽  
B. R. MacIntosh ◽  
W. N. Stainsby
Keyword(s):  
Neuromuscular Block ◽  
Muscle Group ◽  
O2 Uptake ◽  
Plantaris Muscle ◽  
Continuous Stimulation ◽  
Before And After

The purpose of this study was to investigate the effect of changes in developed tension on the ratio between O2 uptake and isometric developed tension in the in situ dog gastrocnemius-plantaris muscle group. O2 uptake and isometric developed tension of the muscle were measured during contractions at 1 twitch/s before and after fatigue with both single and twin impulses (6.5 V, 0.2-ms duration; the twins were separated by 10--20 ms). Twin impulses prior to fatigue raised developed tension to two times the tension developed with single impulses. Fatigue was obtained by stimulation at 10--20 impulses/s for 30--40 min. Twin impulses after fatigue returned developed tension to the level of single impulses before fatigue. O2 uptake and developed tension were also measured during the slower development of fatigue produced by continuous stimulation (3, 4, 5, and 6 impulses/s) as well as during “fatigue” induced by partial neuromuscular block with curare or ischemia. In all cases, there was no change in the O2 uptake per unit of tension developed, indicating a constant coupling between O2 uptake and developed tension.

Effects of reduced O2 delivery with anemia, hypoxia, or ischemia on peak VO2 and force in skeletal muscle

1993 ◽  
Vol 74 (1) ◽  
pp. 186-191 ◽  
Author(s):  
S. L. Dodd ◽  
S. K. Powers ◽  
E. Brooks ◽  
M. P. Crawford
Keyword(s):  
Venous Blood ◽  
Random Order ◽  
O2 Uptake ◽  
Plantaris Muscle ◽  
Experimental Conditions ◽  
Tension Development ◽  
O2 Concentration ◽  
O2 Delivery ◽  
Stimulation Pattern

This investigation was designed to describe alterations in O2 uptake (VO2) and tension development in a contracting in situ gastrocnemious-plantaris muscle preparation during three conditions of reduced O2 delivery [arterial O2 concentration X blood flow (Q)]. The three conditions, hypoxemia (H), ischemia (I), and anemia (A), were matched for O2 delivery. A normoxic normal flow condition was also utilized for comparison. H was produced by respiring the animals with 9% O2 in N2; I was produced by lowering Q, and A was produced by hemodilution with 6% dextran. The stimulation pattern for the isometric tetanic contractions used was 1 train/s, and each train was 200 ms, 70 Hz, and 6 V. The muscle was maximally contracted during each of the experimental conditions, and the conditions were administered in random order. In each bout the contractions continued for 5 min with 30 min of rest between bouts. Samples of arterial and muscle venous blood were obtained during the last 30 s of each bout. VO2 during I (125 ml.kg-1.min-1) was less than during N (145 ml.kg-1.min-1; P < 0.05) and greater than during H or A (104 and 101 ml.kg-1.min-1, respectively; P < 0.05). Venous PO2 (PVO2) was significantly lower during H (17.1 Torr) compared with the other conditions; no differences existed between N, I, and A (26.8, 26.0, and 28.1 Torr, respectively). Tension development was reduced by the reduction of O2 delivery during I, H, and A compared with N. Tension developed among the reduced O2 delivery groups was not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

Net O2, CO2, lactate, and acid exchange by muscle during progressive working contractions

1984 ◽  
Vol 56 (1) ◽  
pp. 161-165 ◽  
Author(s):  
S. J. Chirtel ◽  
R. W. Barbee ◽  
W. N. Stainsby
Keyword(s):  
Acid Output ◽  
Motor Nerve ◽  
Venous Blood ◽  
Work Rate ◽  
O2 Uptake ◽  
Plantaris Muscle ◽  
Independent Variables ◽  
Co2 Output ◽  
Lactate Output ◽  
Acid Exchange

The net O2 uptake (VO2), CO2 output (VCO2), lactate output (L), and non-CO2 acid output (HA) by the gastrocnemius-plantaris muscle group of the dog were measured during progressively loaded isotonic tetanic contractions. Shortening during the 1/s contractions was maintained constant as load was increased by raising the stimulus voltage applied to the motor nerve. Contractions at each load continued for 5 min with two arterial and four venous blood samples obtained during the last minute at each load. Work rate (W) during the contractions was calculated from the load and the shortening. The VO2 increased linearly with time and W. The VCO2 generally followed VO2 with a modest lag during the first two work periods. L increased with time, W, and VO2. Maximal L was lower than that seen during repetitive maximal twitch contractions. HA also increased with time, W, and VO2 and was much larger than L at the higher work rates. It is concluded that L and HA are independent variables during progressive working contractions, as they were during repetitive twitch contractions. Both L and HA patterns may be explained as summations of the respective exchanges of L and HA with time by sequentially recruited groups of muscle fibers.

ADRENAL 17-HYDROXYCORTICOSTEROID SECRETION IN THE DOG IN RESPONSE TO ETHANOL

1972 ◽  
Vol 70 (4) ◽  
pp. 736-740 ◽  
Author(s):  
T. Suzuki ◽  
R. Higashi ◽  
T. Hirose ◽  
H. Ikeda ◽  
K. Tamura
Keyword(s):  
Venous Blood ◽  
Secretion Rate ◽  
Conscious Dogs ◽  
Blood Samples ◽  
Before And After

ABSTRACT Conscious dogs were infused intravenously with ethanol in doses of 0.7 and 1.0 g/kg. The adrenal venous blood samples were collected before and after the infusion of ethanol and analysed for 17-hydroxycorticosteroids (17-OHCS). After the infusion of 0.7 g/kg (subanaesthetic dose) of ethanol the adrenal 17-OHCS secretion rate showed either a slight increase or no change. After the infusion of 1.0 g/kg (anaesthetic dose) of ethanol the adrenal 17-OHCS secretion rate increased markedly and reached 1.21±0.15 (mean±sem) μg/kg/min, while it was 0.09±0.023 μg/kg/min before the infusion.

Blood flow elevation increases VO2 maximum during repetitive tetanic contractions of dog muscle in situ

1993 ◽  
Vol 74 (4) ◽  
pp. 1499-1503 ◽  
Author(s):  
W. F. Brechue ◽  
B. T. Ameredes ◽  
G. M. Andrew ◽  
W. N. Stainsby
Keyword(s):  
Blood Flow ◽  
Perfusion Pressure ◽  
Power Production ◽  
Arterial Supply ◽  
O2 Uptake ◽  
Plantaris Muscle ◽  
Control Series ◽  
Flow Through ◽  
Series Of Experiments

Blood flow through the gastrocnemius-plantaris muscle of the dog in situ was increased by a pump in the arterial supply during a 30-min period of 1/s isotonic tetanic contractions. Compared with a control series of experiments with normoxemia and spontaneous flow, the pump increased flow 84%, from 1.51 +/- 0.08 to 2.78 +/- 0.15 ml.g-1.min-1. The perfusion pressure was increased from 125 to 196 mmHg. The pump hyperemia increased maximal O2 uptake (VO2) at 5 min of contractions by 31%, from 8.97 +/- 0.44 to 12.89 +/- 0.30 mumol.g-1.min-1. The extraction was decreased, and venous PO2 (PVO2) was increased. Fatigue, measured as a drop in power production from the highest level at 10 s to 30 min, was 49% during pump hyperemia and 54% in the control conditions. VO2 decreased 30% from the 5-min value to the 30-min value with pump hyperemia and 28% over the same time in the control conditions. At maximal VO2, the ratio VO2/PVO2 was increased by pump hyperemia compared with control conditions, suggesting an increased O2 diffusing conductance of the muscles. We conclude that the elevated perfusion pressure of pump hyperemia increased flow to raise maximal VO2 mainly in areas of the muscle that had restricted flow under control conditions.

Maximal O2 uptake of in situ dog muscle during acute hypoxemia with constant perfusion

1990 ◽  
Vol 69 (2) ◽  
pp. 570-576 ◽  
Author(s):  
M. C. Hogan ◽  
D. E. Bebout ◽  
P. D. Wagner ◽  
J. B. West
Keyword(s):  
Blood Flow ◽  
Muscle Blood Flow ◽  
Peripheral Tissue ◽  
Diffusing Capacity ◽  
O2 Uptake ◽  
Lactate Output ◽  
O2 Diffusion ◽  
Arterial Po2 ◽  
Different Levels

We investigated the relationships among maximal O2 uptake (VO2max), effluent venous PO2 (PvO2), and calculated mean capillary PO2 (PCO2) in isolated dog gastrocnemius in situ as arterial PO2 (PaO2) was progressively reduced with muscle blood flow held constant. The hypothesis that VO2max is determined in part by peripheral tissue O2 diffusion predicts proportional declines in VO2max and PCO2 if the diffusing capacity of the muscle remains constant. The inspired O2 fraction was altered in each of six dogs to produce four different levels of PaO2 [22 +/- 2, 29 +/- 1, 38 +/- 1, and 79 +/- 4 (SE) Torr]. Muscle blood flow, with the circulation isolated, was held constant at 122 +/- 15 ml.100 g-1.min-1 while the muscle worked maximally (isometric twitches at 5-7 Hz) at each of the four different values of PaO2. Arterial and venous samples were taken to measure lactate, pH, PO2, PCO2, and muscle VO2. PCO2 was calculated using Fick's law of diffusion and a Bohr integration procedure. VO2max fell progressively (P less than 0.01) with decreasing PaO2. The decline in VO2max was proportional (R = 0.99) to the fall in both muscle PvO2 and calculated PCO2 while the calculated muscle diffusing capacity was not different among the four conditions. Fatigue developed more rapidly with lower PaO2, although lactate output from the muscle was not different among conditions. These results are consistent with the hypothesis that resistance to O2 diffusion in the peripheral tissue may be a principal determinant of VO2max.

scholarly journals Posttonsillectomy Bacteremia and Comparison of Tonsillar Surface and Deep Culture

2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Mahmood Shishegar ◽  
Mohammad Javad Ashraf
Keyword(s):  
Venous Blood ◽  
Blood Cultures ◽  
Chronic Tonsillitis ◽  
Blood Samples ◽  
Hemolytic Streptococcus ◽  
Microbiological Study ◽  
Common Organism ◽  
Before And After ◽  
Deep Culture ◽  
Time Of Operation

Objective.This study aimed to identify the microorganisms of surface and depth of tonsils and whether these microorganisms bring the menace of bacteremia during tonsillectomy in the children under surgery.Materials and Methods.The culture specimens were taken from surface and depth of tonsil from the patients suffering from chronic tonsillitis at the time of operation. Also, 10 mL venous blood samples were taken 5 minutes before and after the operation for microbiological study.Results.According to the results, 112 (76.1%) and 117 (79.6%) cultures from surface and depth of tonsils represented multiple microorganisms, respectively. Besides, staphylococci coagulase positive was the most common organism in both surface and depth of tonsils. None of the preoperation blood cultures were positive, while 3 postoperation blood cultures (2.1%) were positive. Staphylococci coagulase negative and alpha hemolytic streptococcus were detected in 2 cases (1.4%) and 1 case (0.7%), respectively.Conclusion.In the present study, the two cultured sites were almost similar regarding the types of isolated microorganisms. Our results suggested that bacteremia might occur after tonsillectomy. Therefore, to avoid the possible dramatic outcomes after tonsillectomy, pre- and postoperation attendances are essential.

scholarly journals Micro-RNAs miR-375-3p and miR-7-5p are released alongside ACTH from corticotroph pituitary neuroendocrine tumor

2021 ◽  
Author(s):  
Helvijs Niedra ◽  
Raitis Peculis ◽  
Ilze Konrade ◽  
Inga Balcere ◽  
Mihails Romanovs ◽  
...  
Keyword(s):  
Expression Patterns ◽  
Venous Blood ◽  
Differential Expression Analysis ◽  
Circulating Mirnas ◽  
Blood Samples ◽  
Peripheral Plasma ◽  
Bodily Fluids ◽  
Micro Rnas ◽  
Before And After ◽  
Acth Secreting

Objective: Circulating miRNAs are found in bodily fluids including plasma and can serve as biomarkers for diseases. The aim of this study was to provide the first insight into the landscape of circulating miRNAs in close proximity to the adrenocorticotropic hormone (ACTH) secreting PitNET. To achieve this objective next-generation sequencing of miRNAs in plasma from bilateral inferior petrosal sinus sampling (BIPSS) - a gold standard in diagnosing ACTH-secreting PitNETs, was carried out. Methods: Sinistral (left) and dextral (right) BIPSS blood samples of the patient were collected in three time points: before the administration of corticotropin-releasing hormone, 5 and 15 minutes after stimulation. Peripheral venous blood samples were also collected 24 hours before and after BIPSS and before the resection of PitNET and 24 hours after. In differential expression analysis sinistral plasma was compared with dextral. Results: BIPSS concluded that the highest amount of ACTH was released in the sinistral side at the 5th minute mark indicating a presence of tumor. The highest amount of differentially expressed miRNAs was observed 5 minutes after stimulation (20 upregulated, 14 downregulated). At the 5th minute mark in sinistral plasma, two miRNAs were identified: hsa-miR-7-5p and hsa-miR-375-3p that were highly upregulated compared to other BIPSS samples and peripheral plasma samples. Clustering analysis showed that BIPSS plasma differs from peripheral plasma in miRNA expression patterns. Conclusions: data indicates that ACTH-secreting PitNET actively releases two circulating miRNAs upon stimulation with CRH (hsa-mir-7-5p, hsa-mir-375-3p) alongside with ACTH implying further studies of these miRNA as diagnostic markers are needed.

Metabolic response to maximal exercise of 800 and 2,000 m in the thoroughbred horse

1987 ◽  
Vol 63 (1) ◽  
pp. 12-19 ◽  
Author(s):  
R. C. Harris ◽  
D. J. Marlin ◽  
D. H. Snow
Keyword(s):  
Uric Acid ◽  
Maximal Exercise ◽  
Metabolic Response ◽  
Venous Blood ◽  
Glycerol Content ◽  
Muscle Lactate ◽  
Blood Samples ◽  
Thoroughbred Horse ◽  
Exercise Muscle ◽  
Muscle Biopsies

To define the metabolic response to maximal exercise in the thoroughbred horse under field conditions, muscle biopsies and venous blood samples were taken from five horses after a single 800-m gallop and from four horses after a single 2,000-m gallop. Muscle and blood samples were also collected during 60 min of recovery. After exercise muscle ATP contents were decreased by 30 +/- 7 (SD) and 47 +/- 3% after the 800- and 2,000-m gallops, respectively. As indicators of purine catabolism, ammonia and uric acid increased in plasma, the accumulation being greater after the 2,000-m gallop. Blood ammonia peaked immediately after exercise and uric acid after 40–60 min of recovery. Muscle glycogen utilization over the 800- and 2,000-m gallops averaged 2.68 +/- 0.90 and 1.06 +/- 0.12 mmol glucosyl units.kg dry muscle-1.s-1, respectively, and the total used amounted to 27.3 +/- 6.6 and 32.5 +/- 8.8% of the initial store. Muscle lactate accumulation averaged 123.5 +/- 49.7 and 167.3 +/- 20.7 mmol/kg dry muscle, respectively, and declined during recovery with half times of 22.9 +/- 4.2 and 18.9 +/- 6.6 min. Blood lactate peaked 5–10 min after exercise. Exercise resulted in only a small increase in muscle glycerol content, but this continued to rise during recovery reaching 9–12 mmol/kg dry muscle after 20 min. During this time the increase in muscle glycerol content exactly matched the decline in glycerol 3-phosphate.

Acute exercise improves serum adiponectin not leptin in sedentary adult obese men

2012 ◽  
Vol 1 (6) ◽  
pp. 298-304
Author(s):  
Eizadi Mojtaba ◽  
Kohandel Mahdi ◽  
Kasbparast JR Mehdi ◽  
Sarshin Amir
Keyword(s):  
Acute Exercise ◽  
Venous Blood ◽  
Serum Adiponectin ◽  
Acute Bout ◽  
Blood Samples ◽  
Serum Leptin ◽  
Before And After ◽  
Obese Subjects ◽  
Short Time ◽  
Inflammation Cytokines

 Leptin and adiponectin, adipose tissue secreted cytokines, play key role inobesity and cardiovascular disease. Although the physiopathological mechanisms underlying these associations are largely unknown. Venous blood samples were obtained before and after an acute bout of moderate cycling test in eighty non‐trained adult obese men (BMI: 33.54 ± 3.43 kg/m2) that participated in this study by accidentally. Blood samples were used for measuring serum leptin and adiponectin. No significant differences were found in serum leptin by cycling exercise with compared to baseline (P ≥ 0.05). But, serum adiponectin levels were significantly increased in response to acute exercise when compared with baseline levels (P < 0.05). Based on these data, we can say, although inflammation cytokines such as leptin does not affect by acute exercise for short time, but it seems that this exercise can increase anti‐inflamatory cytokines as adiponectin in obese subjects. The findings of this study indicate the fact that in response to short‐term exercise, changes in serum adiponectin levels are independent of the leptin response.

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