Arterial Lactate and Pyruvate Concentration in the Normal and Asphyxiated Newborn Infant1

2015 ◽  
pp. 56-68 ◽  
Author(s):  
Lars-Eric Bratteby ◽  
Sten Swanstr�m
Keyword(s):  
Arterial Lactate ◽  
Lactate And Pyruvate

Splanchnic and muscle fructose metabolism during and after exercise

1990 ◽  
Vol 69 (4) ◽  
pp. 1244-1251 ◽  
Author(s):  
G. Ahlborg ◽  
O. Bjorkman
Keyword(s):  
Respiratory Exchange Ratio ◽  
O2 Consumption ◽  
Bicycle Exercise ◽  
Arterial Lactate ◽  
Leg Exercise ◽  
Lactate And Pyruvate ◽  
Leg Muscle ◽  
Glucose Output ◽  
Resting Muscle ◽  
Arterial Glucose

Regional substrate exchange was studied in 12 healthy males during 90 min of bicycle exercise at 30% of maximal O2 consumption with a 20-min recovery. Six subjects received an intravenous fructose infusion (8.5 mmol/min) from 40 min of exercise to the end of recovery. Splanchnic glucose output, muscle glucose uptake, arterial glucose, and insulin were uninfluenced by the infusion. The respiratory exchange ratio rose to 0.93 +/- 0.04, and arterial free fatty acids fell by 50% (P less than 0.05). Fructose was taken up by splanchnic tissues (45% of administered load), leg muscle (28%), and resting muscle (28%). During infusion, arterial lactate and pyruvate rose two- to threefold, and these substrates were released from splanchnic tissues and taken up by exercising and resting muscle. Splanchnic release of lactate, pyruvate, and glucose accounted for 78% of fructose uptake at 90 min of exercise. Uptake of fructose, lactate, and pyruvate accounted for 55% and together with glucose for 103% of the total oxidative metabolism by exercising muscle. The regional fructose uptakes and lactate exchanges persisted throughout recovery. The present results indicate that fructose infusion during leg exercise 1) results in increased carbohydrate oxidation from fructose, lactate, and pyruvate in exercising muscle, 2) exerts a glycogenic effect in resting muscle and liver during exercise and in liver and muscle recovering from exercise, and 3) does not interfere with glucose metabolism, and that fructose transport into muscle differs from that of glucose.

Pyruvate shuttling during rest and exercise before and after endurance training in men

2004 ◽  
Vol 97 (1) ◽  
pp. 317-325 ◽  
Author(s):  
Gregory C. Henderson ◽  
Michael A. Horning ◽  
Steven L. Lehman ◽  
Eugene E. Wolfel ◽  
Bryan C. Bergman ◽  
...  
Keyword(s):  
Endurance Training ◽  
Exercise Intensity ◽  
Glycolytic Flux ◽  
Arterial Lactate ◽  
Arterial Blood ◽  
Before And After ◽  
Isotopic Equilibration ◽  
Lactate And Pyruvate ◽  
Net Release ◽  
Rest And Exercise

We describe the isotopic exchange of lactate and pyruvate after arm vein infusion of [3-13C]lactate in men during rest and exercise. We tested the hypothesis that working muscle (limb net lactate and pyruvate exchange) is the source of the elevated systemic lactate-to-pyruvate concentration ratio (L/P) during exercise. We also hypothesized that the isotopic equilibration between lactate and pyruvate would decrease in arterial blood as glycolytic flux, as determined by relative exercise intensity, increased. Nine men were studied at rest and during exercise before and after 9 wk of endurance training. Although during exercise arterial pyruvate concentration decreased to below rest values ( P < 0.05), pyruvate net release from working muscle was as large as lactate net release under all exercise conditions. Exogenous (arterial) lactate was the predominant origin of pyruvate released from working muscle. With no significant effect of exercise intensity or training, arterial isotopic equilibration [(IEpyruvate/IElactate)·100%, where IE is isotopic enrichment] decreased significantly ( P < 0.05) from 60 ± 3.1% at rest to an average value of 12 ± 2.7% during exercise, and there were no changes in femoral venous isotopic equilibration. These data show that 1) the isotopic equilibration between lactate and pyruvate in arterial blood decreases significantly during exercise; 2) working muscle is not solely responsible for the decreased arterial isotopic equilibration or elevated arterial L/P occurring during exercise; 3) working muscle releases similar amounts of lactate and pyruvate, the predominant source of the latter being arterial lactate; 4) pyruvate clearance from blood occurs extensively outside of working muscle; and 5) working muscle also releases alanine, but alanine release is an order of magnitude smaller than lactate or pyruvate release. These results portray the complexity of metabolic integration among diverse tissue beds in vivo.

scholarly journals A model for measurement of lactate disappearance with isotopic tracers in the steady state

1988 ◽  
Vol 256 (3) ◽  
pp. 1035-1038 ◽  
Author(s):  
W C Stanley ◽  
S L Lehman
Keyword(s):  
Steady State ◽  
Infusion Rate ◽  
Specific Radioactivity ◽  
Compartment Model ◽  
The Body ◽  
Total Carbon ◽  
Isotopic Tracers ◽  
Arterial Lactate ◽  
Lactate And Pyruvate ◽  
Almost All

1. The irreversible disappearance of lactate carbon from the body (RdL) is commonly calculated from data obtained with a continuous infusion of isotopically labelled lactate tracer. The tracer infusion rate divided by the steady-state lactate specific radioactivity in blood is taken to give the rate of lactate disappearance. 2. Measurement of lactate disappearance is complicated by the fact that it is reversibly converted into pyruvate as well as being irreversibly removed from the system. 3. We analysed a four-compartment model of lactate metabolism, representing blood lactate, tissue lactate and pyruvate carbon pools. 4. The standard method of calculating RdL from the lactate tracer infusion rate divided by the specific radioactivity of lactate was not validated. 5. We found that RdL can be calculated from the infusion rate and the pyruvate specific radioactivity, multiplied by the fraction of the total carbon flow out of pyruvate that goes to lactate. 6. Therefore, if almost all of the pyruvate carbon flows back to lactate, then RdL approaches the tracer infusion rate divided by the pyruvate specific radioactivity. On the other hand, if the rate of oxidation is large in relation to the rate of pyruvate conversion into lactate, than RdL is overestimated when calculated from the pyruvate specific radioactivity. 7. Calculation of RdL with the arterial lactate specific radioactivity results in an underestimate of the true RdL.

scholarly journals LACTATE AND PYRUVATE IN BLOOD AND URINE AFTER EXERCISE

1937 ◽  
Vol 118 (2) ◽  
pp. 427-432
Author(s):  
R.E. Johnson ◽  
H.T. Edwards
Keyword(s):  
Lactate And Pyruvate

Effect of metabolites on ε-N-hydroxylysine formation in cell-free extracts of Aerobacter aerogenes 62-1

1977 ◽  
Vol 55 (6) ◽  
pp. 625-629 ◽  
Author(s):  
G. J. Murray ◽  
G. E. D. Clark ◽  
M. A. Parniak ◽  
T. Viswanatha
Keyword(s):  
Enzymatic Activity ◽  
Hydroxy Derivative ◽  
Differential Centrifugation ◽  
Hydroxylase Activity ◽  
Aerobacter Aerogenes ◽  
Lactate And Pyruvate ◽  
First Time

The conversion of L-lysine to its corresponding ε-N-hydroxy derivative has been achieved for the first time by cell-free extracts of Aerobacter aerogenes 62-1. Partial fractionation by differential centrifugation (at 12 000 × g) revealed that both supernatant and pellet are essential for maximum enzymatic activity. The ω-N-hydroxylase (EC 1.14.99) was found to function optimally at pH 7–7.5 and exhibited an apparent Km of about 75 μM for L-lysine. L(+)-Lactate or DL-lactate and pyruvate greatly stimulate the ω-N-hydroxylase activity. The system is strongly inhibited by arsenite and sulfite.

Early Arterial Lactate and Prediction of Outcome in Preterm Neonates Admitted to a Neonatal Intensive Care Unit

2003 ◽  
Vol 83 (3) ◽  
pp. 171-176 ◽  
Author(s):  
Floris Groenendaal ◽  
Caroline Lindemans ◽  
Cuno S.P.M. Uiterwaal ◽  
Linda S. de Vries
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Neonatal Intensive Care Unit ◽  
Neonatal Intensive Care ◽  
Preterm Neonates ◽  
Prediction Of Outcome ◽  
Arterial Lactate

scholarly journals Leg and arm lactate and substrate kinetics during exercise

2003 ◽  
Vol 284 (1) ◽  
pp. E193-E205 ◽  
Author(s):  
G. van Hall ◽  
M. Jensen-Urstad ◽  
H. Rosdahl ◽  
H.-C. Holmberg ◽  
B. Saltin ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Glucose Uptake ◽  
Muscle Mass ◽  
Lactate Concentration ◽  
Whole Body ◽  
Glucose Turnover ◽  
Lactate Oxidation ◽  
Arterial Lactate ◽  
Lactate Uptake ◽  
High Lactate

To study the role of muscle mass and muscle activity on lactate and energy kinetics during exercise, whole body and limb lactate, glucose, and fatty acid fluxes were determined in six elite cross-country skiers during roller-skiing for 40 min with the diagonal stride (Continuous Arm + Leg) followed by 10 min of double poling and diagonal stride at 72–76% maximal O2 uptake. A high lactate appearance rate (Ra, 184 ± 17 μmol · kg−1 · min−1) but a low arterial lactate concentration (∼2.5 mmol/l) were observed during Continuous Arm + Leg despite a substantial net lactate release by the arm of ∼2.1 mmol/min, which was balanced by a similar net lactate uptake by the leg. Whole body and limb lactate oxidation during Continuous Arm + Leg was ∼45% at rest and ∼95% of disappearance rate and limb lactate uptake, respectively. Limb lactate kinetics changed multiple times when exercise mode was changed. Whole body glucose and glycerol turnover was unchanged during the different skiing modes; however, limb net glucose uptake changed severalfold. In conclusion, the arterial lactate concentration can be maintained at a relatively low level despite high lactate Ra during exercise with a large muscle mass because of the large capacity of active skeletal muscle to take up lactate, which is tightly correlated with lactate delivery. The limb lactate uptake during exercise is oxidized at rates far above resting oxygen consumption, implying that lactate uptake and subsequent oxidation are also dependent on an elevated metabolic rate. The relative contribution of whole body and limb lactate oxidation is between 20 and 30% of total carbohydrate oxidation at rest and during exercise under the various conditions. Skeletal muscle can change its limb net glucose uptake severalfold within minutes, causing a redistribution of the available glucose because whole body glucose turnover was unchanged.

scholarly journals Outcomes of severe systemic rheumatic disease patients requiring extracorporeal membrane oxygenation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pierre Bay ◽  
Guillaume Lebreton ◽  
Alexis Mathian ◽  
Pierre Demondion ◽  
Cyrielle Desnos ◽  
...  
Keyword(s):  
Extracorporeal Membrane Oxygenation ◽  
Hospital Mortality ◽  
Critically Ill ◽  
Left Ventricular ◽  
Arterial Lactate ◽  
Saps Ii ◽  
Membrane Oxygenation ◽  
Saps Ii Score ◽  
Va Ecmo ◽  
Vv Ecmo

Abstract Background Systemic rheumatic diseases (SRDs) are a group of inflammatory disorders that can require intensive care unit (ICU) admission because of multiorgan involvement with end-organ failure(s). Critically ill SRD patients requiring extracorporeal membrane oxygenation (ECMO) were studied to gain insight into their characteristics and outcomes. Methods This French monocenter, retrospective study included all SRD patients requiring venovenous (VV)- or venoarterial (VA)-ECMO admitted to a 26-bed ECMO-dedicated ICU from January 2006 to February 2020. The primary endpoint was in-hospital mortality. Results Ninety patients (male/female ratio: 0.5; mean age at admission: 41.6 ± 15.2 years) admitted to the ICU received VA/VV-ECMO, respectively, for an SRD-related flare (n = 69, n = 38/31) or infection (n = 21, n = 10/11). SRD was diagnosed in-ICU for 31 (34.4%) patients. In-ICU and in-hospital mortality rates were 48.9 and 51.1%, respectively. Nine patients were bridged to cardiac (n = 5) or lung transplantation (n = 4), or left ventricular assist device (n = 2). The Cox multivariable model retained the following independent predictors of in-hospital mortality: in-ICU SRD diagnosis, day-0 Simplified Acute Physiology Score (SAPS) II score ≥ 70 and arterial lactate ≥ 7.5 mmol/L for VA-ECMO–treated patients; diagnosis other than vasculitis, day-0 SAPS II score ≥ 70, ventilator-associated pneumonia and arterial lactate ≥ 7.5 mmol/L for VV-ECMO–treated patients. Conclusions ECMO support is a relevant rescue technique for critically ill SRD patients, with 49% survival at hospital discharge. Vasculitis was independently associated with favorable outcomes of VV-ECMO–treated patients. Further studies are needed to specify the role of ECMO for SRD patients.

Sign in / Sign up

Export Citation Format

Share Document