Mechanisms that elevate the glucose concentration of muscle and liver in yellow perch (Perca flavescens Mitchill) after exercise–handling stress

1991 ◽  
Vol 69 (2) ◽  
pp. 456-461 ◽  
Author(s):  
Karl Schwalme ◽  
William C. Mackay
Keyword(s):  
Glucose Concentration ◽  
Yellow Perch ◽  
Liver Glycogen ◽  
Muscle Lactate ◽  
Glucose Content ◽  
Handling Stress ◽  
Cori Cycle ◽  
Wet Weight ◽  
Lactate And Pyruvate ◽  
Total Muscle

To identify the mechanisms that elevate the glucose concentration of muscle and liver in yellow perch after exercise–handling, we exercised–handled perch for 10 min and measured subsequent changes in the glucose, glycogen, lactate, and pyruvate content of liver and muscle. By 15 min after the start of exercise–handling, the average glucose concentration had increased from 40 to 200 mg/100 g in liver, from about 6 to 18 mg/100 g in muscle, and in one of two experiments the average liver glycogen level declined from 4.0 to 2.2% wet weight. The increases in liver and muscle glucose content within 15 min were too large to be accounted for by the disappearance of muscle lactate (via the Cori cycle) and likely resulted from glycogenolysis or gluconeogenesis (from nonlactate substrates) in the liver. However, the Cori cycle, gluconeogenesis from glycerol and amino acids, and inhibition of glucose catabolism by preferential oxidation of lactate could all have contributed to prolonging hyperglycemia in muscle and liver, which lasted more than 12 h. Perch excreted about 7% of the total muscle lactate burden produced during exercise–handling stress.

scholarly journals Cultivation of Saccharomyces cerevisiae with Feedback Regulation of Glucose Concentration Controlled by Optical Fiber Glucose Sensor

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 565
Author(s):  
Lucie Koštejnová ◽  
Jakub Ondráček ◽  
Petra Majerová ◽  
Martin Koštejn ◽  
Gabriela Kuncová ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Optical Fiber ◽  
Glucose Concentration ◽  
Glucose Sensor ◽  
Ruthenium Complex ◽  
Feedback Regulation ◽  
Regulation System ◽  
Sensitive Layer ◽  
Average Deviation ◽  
Glucose Content

Glucose belongs among the most important substances in both physiology and industry. Current food and biotechnology praxis emphasizes its on-line continuous monitoring and regulation. These provoke increasing demand for systems, which enable fast detection and regulation of deviations from desired glucose concentration. We demonstrated control of glucose concentration by feedback regulation equipped with in situ optical fiber glucose sensor. The sensitive layer of the sensor comprises oxygen-dependent ruthenium complex and preimmobilized glucose oxidase both entrapped in organic–inorganic polymer ORMOCER®. The sensor was placed in the laboratory bioreactor (volume 5 L) to demonstrate both regulations: the control of low levels of glucose concentrations (0.4 and 0.1 mM) and maintenance of the glucose concentration (between 2 and 3.5 mM) during stationary phase of cultivation of Saccharomyces cerevisiae. Response times did not exceed 6 min (average 4 min) with average deviation of 4%. Due to these regulation characteristics together with durable and long-lasting (≥2 month) sensitive layer, this feedback regulation system might find applications in various biotechnological processes such as production of low glucose content beverages.

L-Lactic Acid’s Improvement of Swimming Endurance in Mice

2009 ◽  
Vol 19 (6) ◽  
pp. 673-684 ◽  
Author(s):  
Guihua Zhang ◽  
Nobuya Shirai ◽  
Hiramitsu Suzuki
Keyword(s):  
Lactic Acid ◽  
Biochemical Parameters ◽  
Liver Glycogen ◽  
Nonesterified Fatty Acid ◽  
Saline Injection ◽  
Muscle Lactate ◽  
Swimming Time ◽  
Biochemical Analyses ◽  
Swimming Endurance ◽  
Dose Dependent

The aim of this study was to investigate the effect of L-lactic acid on swimming endurance of mice. Mice (n = 50) were injected intraperitoneally with saline, then with L-lactic acid (either 25 mg/kg or 50 mg/kg body weight), then after 2 days with the same doses of glucose, and after another 2 days again with L-lactic acid at the same doses. Swimming times to exhaustion were determined at 30 min after each injection, in a tank filled with 25 cm of water maintained at 23 °C. After another week, mice were given either saline, L-lactic acid, or glucose (25 or 50 mg/kg) dissolved in saline and sacrificed after 30 min for biochemical analyses. The ratios of swimming times of L-lactic acid or glucose injections to saline injection were calculated as an index for endurance changes. Swimmingtime ratios for mice injected with L-lactic acid were significantly higher at either dose than for those injected with the corresponding doses of glucose (p < .05). The ratio of swimming time was greater in those given a dose of 50 mg/kg than in those given 25 mg/kg for mice in the L-lactic acid groups (p < .05) but not in the groups given glucose. There were no marked differences in biochemical parameters of plasma and muscle lactate, muscle and liver glycogen, or plasma glucose and nonesterified fatty acid between the L-lactic acid, glucose, and saline injection groups. These results suggest that L-lactic acid can enhance swimming endurance of mice and that this action is dose dependent.

scholarly journals Peritoneal dialysis fluid inhibition of phagocyte function: effects of osmolality and glucose concentration.

1993 ◽  
Vol 3 (8) ◽  
pp. 1508-1515
Author(s):  
T Liberek ◽  
N Topley ◽  
A Jörres ◽  
G A Coles ◽  
G M Gahl ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Lactate Dehydrogenase ◽  
Glucose Concentration ◽  
Lactate Concentration ◽  
Mononuclear Leukocytes ◽  
Dependent Manner ◽  
Dialysis Fluid ◽  
Glucose Content ◽  
Peritoneal Dialysis Fluid ◽  
Dialysis Fluids

Solutions were formulated to examine, independently, the roles of osmolality and glucose in the reduction of viability and inhibition of phagocyte function by dextrose-containing peritoneal dialysis fluids. The exposure of neutrophils (polymorphonuclear leukocytes) to test fluids containing > or = 2.7% (wt/vol) glucose resulted in significant cytotoxicity as assessed by the release of lactate dehydrogenase above control values (7.12 +/- 2.65%). At the highest concentration of glucose (4.5%), lactate dehydrogenase release was 15.83 +/- 0.49% (P < 0.05). These effects were directly related to the presence of D-glucose in the test fluids. In contrast, phagocytosis and the release of leukotriene B4 from PMN stimulated with serum-treated zymosan were significantly inhibited in an osmolality-, but not glucose-, dependent manner. The inhibition of tumor necrosis factor alpha and interleukin-6 release from mononuclear leukocytes was inhibited by a combination of osmolality and monosaccharide concentration. Under the same conditions, PMN respiratory burst activation remained unaffected irrespective of glucose concentration or fluid osmolality. These data indicate that, in addition to the low pH of peritoneal dialysis fluid and its high lactate concentration, its glucose content (either directly or as a consequence of the resulting hyperosmolality of the fluid) inhibits cell functional parameters. These findings suggest clinically significant inhibition of host defense mechanisms because, in high-glucose dialysis fluids, osmolality does not reach physiologic values, even during extended intraperitoneal dwell periods.

scholarly journals IR-Photometry Method for Measuring Glucose Concentration in Peritoneal Dialysis Fluid

2021 ◽  
Vol 24 (4) ◽  
pp. 68-78
Author(s):  
N. M. Zhilo ◽  
M. O. Mikhailov ◽  
E. L. Litinskaia ◽  
K. V. Pozhar
Keyword(s):  
Peritoneal Dialysis ◽  
Optical System ◽  
Glucose Concentration ◽  
Experimental Studies ◽  
The Body ◽  
Artificial Kidney ◽  
Dialysis Fluid ◽  
Glucose Content ◽  
Peritoneal Dialysis Fluid ◽  
Dialysate Solution

Introduction. The transition of glucose into the blood during automated peritoneal dialysis with regeneration of the dialysis fluid leads to a decreased removal of excess fluid from the body and corresponding violations of the water-salt balance.Aim. To consider a system for automatically maintaining the concentration of glucose in the dialysate solution, which provides effective ultrafiltration, as well as to propose a non-contact photometric feedback sensor.Materials and methods. The sensor is an optical system of an IR laser diode with a power of 30 mW and a wavelength of 1600 nm, a photodiode and a quartz tube, through which the test solution circulates. The sensor measures the attenuation of the radiation passing through the solution in a pulsed mode and calculates the glucose concentration. The selected combination of digital filters provides compensation for the noise of the optical system. Experimental studies of the efficiency of the sensor were carried out on peritoneal dialysis solutions with various concentrations of urea, creatinine, uric acid and glucose. At the beginning of the experiments, the sensor was calibrated in a pure solution.Results. It was shown that the developed sensor makes it possible to measure the concentration of glucose in a solution for peritoneal dialysis in the range of 42…220 mmol / l with a relative error of about 15%. The time of one measurement is about 1 minute, which makes it possible to obtain up-to-date information on the current concentration of the solution.Conclusion. This combination of characteristics will allow the sensor to be used in artificial kidney wearable devices for assessing the glucose content in the solution, calculating the time to change the solution and as a feedback sensor in a system for maintaining the concentration of the osmotic agent.

Proceedings of the First International Snakehead Symposium

2019 ◽  
Keyword(s):  
Yellow Perch ◽  
River System ◽  
Potomac River ◽  
Inland Fisheries ◽  
Channa Argus ◽  
Wet Weight ◽  
Virginia Department ◽  
Prey Items ◽  
Lentic Systems ◽  
Banded Killifish

<em>Abstract.</em>—The nonnative Northern Snakehead <em>Channa argus </em>was first documented in the Potomac River system in 2004. Since then, their range in Virginia has expanded to include other rivers and numerous lakes as a result of dispersal and illegal introductions. Most Northern Snakehead lake populations were discovered after 2012. Through 2017, nearly 4,000 Northern Snakehead were collected via Virginia Department of Game and Inland Fisheries (VDGIF) electrofishing surveys, resulting in a robust dataset. These collections provided an opportunity to investigate food habits of Northern Snakehead in both lotic and lentic systems which may assist with management and a better understanding of potential community effects. Incidence of identifiable prey items (<em>n </em>= 677) was evaluated since 2004, however wet weights (<em>n </em>= 370) were not recorded until 2014. A total of 30 prey types were identified from Northern Snakehead stomachs taken from rivers, whereas 7 prey types were identified from lakes. Banded Killifish, Bluegill, and crayfish were the most abundant prey types (in order) based on frequency of occurrence for Northern Snakehead collected from rivers; whereas Bluegill, frogs, and Yellow Perch were most common in Northern Snakehead collected from lakes. Most important food types (in order) based on % wet weight for Northern Snakehead collected from rivers were Bluegill, Gizzard Shad, and Banded Killifish; whereas Bluegill, Yellow Perch, and frogs contributed the most mass for Northern Snakehead from lakes.

Plasma glucose concentration determines direct versus indirect liver glycogen synthesis

1986 ◽  
Vol 251 (5) ◽  
pp. E584-E590 ◽  
Author(s):  
C. H. Lang ◽  
G. J. Bagby ◽  
H. L. Blakesley ◽  
J. L. Johnson ◽  
J. J. Spitzer
Keyword(s):  
Plasma Glucose ◽  
Glucose Concentration ◽  
Infusion Rate ◽  
Glycogen Synthesis ◽  
Liver Glycogen ◽  
Glucose Infusion ◽  
Glucose Infusion Rate ◽  
Hepatic Glycogen ◽  
Glucose Load ◽  
Indirect Pathway

In the present study hepatic glycogenesis by the direct versus indirect pathway was determined as a function of the glucose infusion rate. Glycogen synthesis was examined in catheterized conscious rats that had been fasted 48 h before receiving a 3-h infusion (iv) of glucose. Glucose, containing tracer quantities of [U-14C]- and [6-3H]glucose, was infused at rates ranging from 0 to 230 mumol X min-1 X kg-1. Plasma concentrations of glucose, lactate, and insulin were positively correlated with the glucose infusion rate. Despite large changes in plasma glucose, lactate, and insulin concentrations, the rate of hepatic glycogen deposition (0.46 +/- 0.03 mumol X min-1 X g-1) did not vary significantly between glucose infusion rates of 20 and 230 mumol X min-1 X kg-1. However, the percent contribution of the direct pathway to glycogen repletion gradually increased from 13 +/- 2 to 74 +/- 4% in the lowest to the highest glucose infusion rates, with prevailing plasma glucose concentrations from 9.4 +/- 0.5 to 21.5 +/- 2.1 mM. Endogenous glucose production was depressed (by up to 40%), but not abolished by the glucose infusions. Only a small fraction (7-14%) of the infused glucose load was incorporated into liver glycogen via the direct pathway irrespective of the glucose infusion rate. Our data indicate that the relative contribution of the direct and indirect pathways of hepatic glycogen synthesis are dependent on the glucose load or plasma glucose concentration and emphasize the predominance of the indirect pathway of glycogenesis at plasma glucose concentrations normally observed after feeding.

Evaluation of a dipstick test for glucose in urine.

1976 ◽  
Vol 22 (2) ◽  
pp. 205-210 ◽  
Author(s):  
J Dyerberg ◽  
L Pedersen ◽  
O Aagaard
Keyword(s):  
Diabetes Mellitus ◽  
Total Variation ◽  
Urine Sample ◽  
Glucose Concentration ◽  
Dipstick Test ◽  
Glucose Content ◽  
Modifying Factors ◽  
Urinary Glucose ◽  
Different Types ◽  
Test Result

Abstract As an example of qualitative tests, a dipstick analysis for glucose in urine has been tested for the influence of modifying factors on the test result. Two different types of dipsticks were examined, "Clinistix" and "S-Gluko-test." Used according to manufacturer's instructions, the latter is more sensitive and selective. By multivariance analysis the following variables were examined: urine samples, inter- and intra-analyst, exposure to light, and dipstick batch. The first three contributed significantly to the total variation in results, inter-specimen variation being the most important. With knowledge of the frequency of testing urines with a given glucose concentration and the probability of the result at that concentration, an expression of the probability of the glucose content of a urine sample can be obtained. Even with the tests of the type examined having a sensitivity and specificity exceeding 95%, 14 of 100 patients suspected of having diabetes mellitus on the basis of a dipstick examination will be found to have a urinary glucose concentration of less than 2 mmol/liter. These figures were found when the prevalence of urines with a glucose concentration exceeding 2 mmol/liter was 17.5%.

Prolonged anoxic survival due to anoxia pre-exposure: brain ATP, lactate, and pyruvate

1964 ◽  
Vol 207 (2) ◽  
pp. 452-456 ◽  
Author(s):  
Nancy Ann Dahl ◽  
William M. Balfour
Keyword(s):  
Energy Metabolism ◽  
Survival Time ◽  
Glucose Concentration ◽  
Prolonged Survival ◽  
Anaerobic Glycolysis ◽  
Cerebral Energy Metabolism ◽  
Atp Concentration ◽  
Lactate And Pyruvate ◽  
The Brain

Rats subjected to a brief anoxia can survive go sec in a second anoxia, compared to a 60-sec survival time of control animals. Slower disappearance of ATP concentration in the brain during the second exposure indicates this longer survival is due to an altered cerebral energy metabolism. Initial cerebral ATP concentration is no higher in pre-exposed animals than in controls. When glycolysis is inhibited by iodoacetate before testing in anoxia, the advantage of pre-exposure disappears, suggesting the longer survival may be due to increased anacrobic glycolysis. Lactate accumulates faster during anoxia in the brains of pre-exposed animals than in controls, suggesting that increased anaerobic glycolysis is the cause of the prolonged survival. This effect is not due to increased cerebral glucose concentration. A possible reason for this increased glycolysis, and thus the prolonged survival, could be an increase of a compound, such as pyruvate, capable of oxidizing NADH. The initial pyruvate is higher in pre-exposed animals than in controls and injection of pyruvate increases the survival time slightly.

Mechanism of delayed hepatic glycogen synthesis after an oral galactose load vs. an oral glucose load in adult rats

1992 ◽  
Vol 263 (1) ◽  
pp. E42-E49 ◽  
Author(s):  
C. B. Niewoehner ◽  
B. Neil
Keyword(s):  
Glucose Concentration ◽  
Glycogen Synthesis ◽  
Liver Glycogen ◽  
Hepatic Glycogen ◽  
Oral Glucose ◽  
Glucose Load ◽  
Adult Rats ◽  
Glycogen Accumulation ◽  
Glucose Administration

We have compared the effects of administration of oral galactose or glucose (1 g/kg) to 24-h fasted rats to examine the mechanism by which galactose regulates its own incorporation into liver glycogen in vivo. Liver glycogen increased to a maximum more slowly after galactose than after glucose administration (0.14 vs. 0.29 mumol.g liver-1.min-1). Glycogen accumulation after the galactose load was 70% of that after the glucose load (149 vs. 214 mumol), and the net increase in liver glycogen represented the same proportion (24 vs. 22%) of added carbohydrate after urinary loss of galactose was accounted for. Slower glycogen accumulation after galactose vs. glucose loading could not be explained by galactosuria, by differences in the active forms of synthase or phosphorylase, by end product (glycogen) inhibition of synthase phosphatase, or by different concentrations of the known allosteric effectors of synthase R plus I and phosphorylase a. Similar increases in glucose 6-phosphate were observed after both hexoses. AMP and ADP increased only transiently after galactose administration, and ATP, UTP, and Pi concentrations were unchanged. The UDP-glucose concentration decreased, whereas the UDP-galactose concentration increased two- to threefold after galactose but not glucose administration. The UDP-glucose pyrophosphorylase reaction is inhibited competitively by UDP-galactose. This could explain the decreased UDP-glucose concentration and the reduced rate of glycogen synthesis after galactose was given.

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