Differential impairment of thermogenesis in the pigeon after chemical sympathectomy

1978 ◽  
Vol 56 (4) ◽  
pp. 578-584 ◽  
Author(s):  
E. Hohtola ◽  
H. Rintamäki ◽  
R. Hissa
Keyword(s):  
Oxygen Consumption ◽  
Electrical Activity ◽  
Plasma Free Fatty Acid ◽  
Lower Body ◽  
Plasma Lactate ◽  
Chemical Sympathectomy ◽  
Ffa Metabolism ◽  
Lactate Levels ◽  
The Stability ◽  
6 Hydroxydopamine

A dose-controlled chemical sympathectomy with 6-hydroxydopamine (6-OHDA) did not disrupt thermostasis in the pigeon at +38 °C. At +6 °C, thermogenesis was impaired, but the lower body temperature and oxygen consumption were stable and vasoconstriction was normal. The stability may partly be explained by a massive release of adrenaline from the adrenals (50% in 20 min). Despite a deficit in heat production both after sympathectomy and after acute 6-OHDA, no change in muscle electrical activity was observed. Plasma free fatty acid (FFA) concentration was significantly elevated after sympathectomy, but no changes occurred in blood glucose or plasma lactate levels. The results indicate a major compensatory role for the adrenals in avian thermogenesis. They also suggest a sympathetically mediated auxiliary thermogenic mechanism independent of muscle electrical activity and coupled to FFA metabolism.

Relationship Among Recovery Oxygen, Oxygen Missed, Lactate Production and Lactate Removal During and Following Severe Hypoxia in the Unanesthetized Dog

1958 ◽  
Vol 192 (3) ◽  
pp. 585-591 ◽  
Author(s):  
Norman R. Alpert ◽  
Herbert Kayne ◽  
Winona Haslett
Keyword(s):  
Oxygen Consumption ◽  
Significant Relationship ◽  
Recovery Period ◽  
Lactate Production ◽  
Severe Hypoxia ◽  
Plasma Lactate ◽  
Oxygen Oxygen ◽  
Lactate Removal ◽  
Lactate Levels ◽  
Removal And Recovery

An experiment was designed to test the ‘O2debt’ hypothesis. Oxygen consumption and plasma lactate were measured before, during and following hypoixa in unanesthetized spinally transected dogs. The O2 consumption was depressed during hypoxia and returned toward control levels during recovery. Lactate levels increased during the hypoxia and returned to the control during recovery. Oxygen missed was correlated with the excess consumption of recovery. A highly significant relationship was found which indicated that the larger the depression in O2 consumption during hypoxia, the greater was the depression during the recovery period and the more prolonged the return to control levels. Oxygen missed during hypoxia was compared to lactate production. A significant relationship was found. Lactate removal was compared to excess consumption of recovery. No correlation existed between lactate removal and recovery O2 consumption. The authors postulate the presence of a metabolic governor which controls the rate of O2 uptake.

METABOLIC ASPECTS OF DEEP SURGICAL HYPOTHERMIA IN INFANCY

PEDIATRICS ◽  
1968 ◽  
Vol 42 (1) ◽  
pp. 93-105
Author(s):  
David Baum ◽  
David H. Dillard ◽  
Hitoshi Mohri ◽  
Edward W. Crawford
Keyword(s):  
Glucose Utilization ◽  
Circulatory Arrest ◽  
Plasma Free Fatty Acid ◽  
Glycerol Metabolism ◽  
Plasma Lactate ◽  
Ether Anesthesia ◽  
Carbohydrate And Lipid Metabolism ◽  
External Cooling ◽  
Lactate Levels ◽  
General Plasma

Aspects of carbohydrate and lipid metabolism were examined in 10 infants whose core temperatures were lowered by external cooling to 15 to 20°C during cardiovascular surgery. Modest hyperglycemia, found with ether anesthesia, persisted in three patients not given glucose, but it was markedly increased in others given glucose infusions. Despite continued glucose infusion, plasma glucose returned toward prehypothermic levels with rewarming, provided epinephrine was not administered. When epinephrine was given, the return was slowed. These observations suggest diminished glucose utilization during hypothermia and arouse speculation concerning a related insulin abnormality. In general, plasma lactate and glycerol levels increased during hypothermia, reaching a peak after circulatory arrest and with rewarming. Plasma free fatty acid concentrations changed little until rewarming when they usually became depressed. Death occurred in all five infants in whom plasma glycerol and lactate levels were rising at the procedure's end, while plasma glycerol and lactate concentrations were falling on completion of the operation in patients who did well. These findings and the known importance of the liver in lactate and glycerol metabolism suggest that the course of plasma lactate and glycerol levels may prove useful as a reflection of hepatic dysfunction in patients undergoing hypothermic surgery.

scholarly journals Prolonged swimming, recovery and repeat swimming performance of mature sockeye salmon Oncorhynchus nerka exposed to moderate hypoxia and pentachlorophenol.

1998 ◽  
Vol 201 (14) ◽  
pp. 2183-2193 ◽  
Author(s):  
A P Farrell ◽  
A K Gamperl ◽  
I K Birtwell
Keyword(s):  
Oxygen Consumption ◽  
Swimming Speed ◽  
Sockeye Salmon ◽  
Swimming Performance ◽  
Oncorhynchus Nerka ◽  
High Plasma ◽  
Plasma Lactate ◽  
Critical Swimming Speed ◽  
Moderate Hypoxia ◽  
Lactate Levels

Mature, wild sockeye salmon (Oncorhynchus nerka) demonstrated their remarkable stamina and recovery abilities by performing three consecutive critical swimming speed tests with only a 45 min interval for recovery between subsequent tests. Although the repeated swimming challenges were performed without a full recovery, normoxic fish swam just as well on the second swim, and the majority of fish swam only marginally more poorly on the third swim. In addition, metabolic loading in these fish, as measured by the rate of oxygen consumption, ventilation rate and plasma lactate levels during recovery, did not appear to be cumulative with successive swims. Fish, however, did not recover as well after a similar level of initial swimming performance under moderately hypoxic conditions (water PO2>100 mmHg; 1 mmHg=0.1333 kPa). Four out of the five fish did not swim again and their high plasma lactate levels indicated a greater anaerobic effort. In another group of fish, metabolic loading (elevated control rates of oxygen consumption) was induced with an overnight sublethal exposure to pentachlorophenol, but these fish swam as well as normoxic fish on the first swim, and five of the six fish swam for a third time at a marginally lower critical swimming speed. In contrast to expectations, pentachlorophenol pretreatment and moderate hypoxia were not additive in their effects. Instead, the effects resembled those of pentachlorophenol pretreatment alone. The results are discussed in terms of what aspects of fatigue might impair the repeat swimming performance of sockeye salmon.

Response to intravenous injections of amylin and glucagon in fasted, fed, and hypoglycemic rats

1993 ◽  
Vol 264 (6) ◽  
pp. E943-E950 ◽  
Author(s):  
A. A. Young ◽  
G. J. Cooper ◽  
P. Carlo ◽  
T. J. Rink ◽  
M. W. Wang
Keyword(s):  
Plasma Glucose ◽  
Insulin Infusion ◽  
Sodium Lactate ◽  
Plasma Lactate ◽  
Glucose Response ◽  
Intravenous Injections ◽  
Glucose Levels ◽  
Fasted State ◽  
Islet Hormone ◽  
Lactate Levels

The actions of intravenous glucagon and amylin, a newly discovered hyperglycemic pancreatic islet hormone, have been compared in 20-h fasted and fed, lightly anesthetized rats, and in rats made hypoglycemic with an insulin infusion. In fasted animals, amylin (75 nmol/kg) was more effective than glucagon (90 nmol/kg) in increasing plasma glucose (glucose increment 4.55 vs. 1.71 mM, P < 0.001). Amylin elicited a marked increase in plasma lactate, as previously reported, whereas glucagon did not alter plasma lactate. In fed animals, glucagon elicited twice as much increase in plasma glucose as did amylin; amylin again elicited a marked lactate increase that was greater (increment 1.45 vs. 0.97 mM, P < 0.05) and more prolonged than in the fasted state, whereas glucagon was without effect on lactate levels. These findings are consistent with glucagon's known action to promote hyperglycemia from hepatic glycogenolysis and amylin's demonstrated action to promote muscle glycogenolysis and increase lactate supply to the liver. Infusions of sodium lactate that produced plasma lactate increments similar to those evoked by 75 nmol/kg amylin evoked patterns of glucose response in fasted and fed rats similar to those evoked by amylin. Thus increased lactate supply to the liver may account for amylin's hyperglycemic effects. Amylin and glucagon could each restore plasma glucose to control levels in fasted animals made hypoglycemic by insulin infusion (plasma glucose reduced to 3.3 mM). A bolus of 75 nmol/kg amylin was more effective than 180 nmol/kg glucagon, restoring basal glucose levels for > 3 h, whereas glucagon restored it for < 1 h.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Plasma lactate levels and lactate clearance as predictors of outcome in patients with sepsis and septic shock

2020 ◽  
Vol 7 (6) ◽  
pp. 1213
Author(s):  
Rashmi Patil ◽  
Chikkanarasareddy P. S. ◽  
Mallesh K.
Keyword(s):  
Septic Shock ◽  
Clinical Decision Making ◽  
Early Recognition ◽  
Early Stage ◽  
Therapeutic Option ◽  
Lactate Clearance ◽  
Plasma Lactate ◽  
Risk Of Death ◽  
Lactate Levels ◽  
Sepsis And Septic Shock

Background: Severe sepsis and septic shock are the major causes of admission and deaths in the ICU, killing one in four (and often more) and increasing in incidence. In order to improve the clinical outcomes in these patients, it is crucial to obtain early recognition of patients who are at risk of death and to optimize the clinical decision making in a timely manner. In order to monitor the metabolic consequences of shock and hemodynamic management, plasma lactate levels can be used in critical illness. Objective of the study is to estimate plasma lactate and lactate clearance in sepsis and septic shock patients and to correlate plasma lactate and lactate clearance as predictors of mortality.Methods: This study is a prospective observational study conducted over 18months. Children with age of 1 month to 18 years admitted to the Paediatric intensive care unit with sepsis and septic shock were enrolled in the study. ABG at admission to document plasma lactate and lactate repeated at 6 and 24 hrs. Lactate clearance calculated at 6 and 24 hrs. The final outcome in terms of survival or death will be recorded.Results: Majority of the children fall in the class between 1-6 months 51(48.11%). Male comprises 69(65.09%). Among these, Sepsis 36(33.96%); followed by Pneumonia 34(32.07%). Survivors group were 35(33.02%) and non-survivor was 71(66.98%). The Non survivor group was observed to have lower mean values of lactate clearance and found to be statistically significant. Specificity of Lactate clearance was 63.52% and Sensitivity 76.02% respectively. The results were positively associated with lactate level at 24 hours found to be significant effect of survivability when compared to non-survivor.Conclusions: Lactate clearance is vital and markable sign for screening of septic shock at early stage for therapeutic option. Further, 24-hours lactate estimation (cut off values) clearance appears superior to 6 h lactate clearance in predicting mortality in such patients.

scholarly journals Developmental changes in oxygen consumption regulation in larvae of the South African clawed frog Xenopus laevis

1995 ◽  
Vol 198 (12) ◽  
pp. 2465-2475 ◽  
Author(s):  
D Hastings ◽  
W Burggren
Keyword(s):  
Oxygen Consumption ◽  
Lactic Acid ◽  
Xenopus Laevis ◽  
South African ◽  
Acute Hypoxia ◽  
Lactate Concentration ◽  
Aerobic Metabolism ◽  
Whole Body ◽  
Lactate Levels ◽  
Clawed Frog

Well-developed larval Xenopus laevis (NF stages 58&shy;66) are oxygen regulators, at least during mild hypoxia. When and how they change from oxygen conformers (the presumed condition of the fertilized egg) to oxygen regulators is unknown. Also unknown is how anaerobic metabolic capabilities change during development, especially in response to acute hypoxia, and to what extent, if any, anaerobiosis is used to supplement aerobic metabolism. Consequently, we have investigated resting rates of oxygen consumption (M.O2) and concentrations of whole-body lactate (lactic acid) during development in normoxia and in response to acute hypoxia in Xenopus laevis. M.O2 increased in an episodic, non-linear fashion during development. Resting, normoxic M.O2 increased about tenfold (to approximately 0.20 &micro;mol g-1 h-1) between NF stages 1&shy;39 and 40&shy;44, and then another tenfold between NF stages 45&shy;48 and 49&shy;51 (to approximately 2.0 &micro;mol g-1 h-1), remaining at about 2 &micro;mol g-1 h-1 for the remainder of larval development. M.O2 reached its highest level in newly metamorphosed frogs (nearly 4 &micro;mol g-1 h-1), before decreasing to about 1.0 &micro;mol g-1 h-1 in large adults. X. laevis embryos and larvae up to NF stage 54&shy;57 were oxygen conformers when exposed to variable levels of acute hypoxia. The only exception was NF stage 45&shy;48 (external gills present yet body mass still very small), which showed some capability of oxygen regulation. All larvae older than stage 54&shy;57 and adults were oxygen regulators and had the lowest values of Pcrit (the oxygen partial pressure at which M.O2 begins to decline). Whole-body lactate concentration in normoxia was about 1 &micro;mol g-1 for all larval groups, rising to about 12 &micro;mol g-1 in adults. Concentrations of lactic acid in NF stages 1&shy;51 were unaffected by even severe ambient hypoxia. However, whole-body lactate levels in NF stages 52&shy;66 increased in response to severe hypoxia, indicating that some anaerobic metabolism was being used to supplement diminishing aerobic metabolism. The largest increases in concentration of lactate occurred in late larvae and adults.

Activity before exercise influences recovery metabolism in the lizard Dipsosaurus dorsalis

2000 ◽  
Vol 203 (12) ◽  
pp. 1809-1815
Author(s):  
D.A. Scholnick ◽  
T.T. Gleeson
Keyword(s):  
Oxygen Consumption ◽  
Metabolic Rate ◽  
Blood Lactate ◽  
Recovery Period ◽  
Maximal Activity ◽  
Warm Up ◽  
Dipsosaurus Dorsalis ◽  
Rate Of Oxygen Consumption ◽  
Lactate Levels ◽  
Blood Lactate Levels

During recovery from even a brief period of exercise, metabolic rate remains elevated above resting levels for extended periods. The intensity and duration of exercise as well as body temperature and hormone levels can influence this excess post-exercise oxygen consumption (EPOC). We examined the influence of activity before exercise (ABE), commonly termed warm-up in endotherms, on EPOC in the desert iguana Dipsosaurus dorsalis. The rate of oxygen consumption and blood lactate levels were measured in 11 female D. dorsalis (mass 41.1 +/− 3.0 g; mean +/− s.e.m.) during rest, after two types of ABE and after 5 min of exhaustive exercise followed by 60 min of recovery. ABE was either single (15 s of maximal activity followed by a 27 min pause) or intermittent (twelve 15 s periods of exercise separated by 2 min pauses). Our results indicate that both single and intermittent ABE reduced recovery metabolic rate. EPOC volumes decreased from 0.261 to 0.156 ml of oxygen consumed during 60 min of recovery when lizards were subjected to intermittent ABE. The average cost of activity (net V(O2) during exercise and 60 min of recovery per distance traveled) was almost 40 % greater in lizards that exercised without any prior activity than in lizards that underwent ABE. Blood lactate levels and removal rates were greatest in animals that underwent ABE. These findings may be of particular importance for terrestrial ectotherms that typically use burst locomotion and have a small aerobic scope and a long recovery period.

scholarly journals Effects of carbohydrate quality and amount on plasma lactate: results from the OmniCarb trial

2020 ◽  
Vol 8 (1) ◽  
pp. e001457
Author(s):  
Jiun-Ruey Hu ◽  
Yingfei Wu ◽  
Frank M Sacks ◽  
Lawrence J Appel ◽  
Edgar R Miller III ◽  
...  
Keyword(s):  
Glucose Metabolism ◽  
Plasma Lactate ◽  
Obese Adults ◽  
High Carbohydrate ◽  
Term Change ◽  
Carbohydrate Quality ◽  
Low Carbohydrate ◽  
Registration Number ◽  
Lactate Levels ◽  
Design And Methods

IntroductionPlasma lactate is a marker of non-oxidative glucose metabolism associated with progression to diabetes. We examined the effect of carbohydrate quality (glycemic index (GI)) and amount (%kcal) on plasma lactate. We hypothesized that low GI (≤45 (g)) versus high (≥65 (G)) and low %kcal from carbohydrate (40% kcal (c)) versus high (58% kcal (C)) each would reduce lactate levels.Research design and methodsWe measured lactate in OmniCarb, a randomized, cross-over trial of four diets in overweight/obese adults without diabetes or cardiovascular disease (N=163). The four diets were high carbohydrate+high GI (CG, reference), high carbohydrate+low GI (Cg), low carbohydrate+high GI (cG), and low carbohydrate+low GI (cg). Participants (N=163) consumed each of the four diets over a 5-week period, separated by 2-week washout periods. Plasma lactate levels were measured at baseline, during which the participants consumed their own diets, and after each 5-week period.ResultsBaseline plasma lactate was 1.2 mmol/L. In the setting of high carbohydrate amount, reducing GI lowered plasma lactate non-significantly by 0.08 mmol/L (Cg vs CG: 95% CI −0.16 to 0.00; p=0.06). In the setting of high GI, reducing carbohydrate amount lowered plasma lactate by 0.10 mmol/L (cG vs CG: 95% CI −0.19 to −0.02; p=0.02). The combined effect of reducing GI and carbohydrate proportion in the diet (cg vs CG) was similar (cg vs CG: −0.08; 95% CI −0.16 to 0.00; p=0.04). All four diets reduced plasma lactate compared with baseline.ConclusionsCompared with a diet with high GI and high carbohydrate amount, diets with low GI and/or low carbohydrate amount reduced plasma lactate. Whether this change in lactate leads to long-term change in glucose metabolism needs to be examined.Trial registration numberNCT00608049.

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