In Vivo Disposal Kinetics of Blood Glucose Carbon to Hepatic and Non-hepatic Products in Normal and Diabetic Rats

1974 ◽  
Vol 52 (4) ◽  
pp. 797-807 ◽  
Author(s):  
R. A. Shipley ◽  
A. P. Gibbons ◽  
E. B. Chudzik
Keyword(s):  
Glycogen Content ◽  
No Reduction ◽  
Neutral Lipids ◽  
Diabetic Rats ◽  
High Rate ◽  
Hepatic Tissue ◽  
Hepatic Glycogen ◽  
Glucose Carbon ◽  
Kinetics Of

Individual rates of conversion of glucose (carbon) to a variety of products were determined separately for hepatic and non-hepatic tissue in fasted normal and diabetic rats. Because the method requires a sustained sojourn of 14C tracer in a conversion product, curves of accumulation of 14C during 6–8 h were obtained for each product. For non-hepatic tissue a satisfactory rise to a sustained level was observed for all products in normals and diabetics, but in the case of liver such behavior was observed only for glycogen in diabetics, neutral lipids in normals, and protein and phospholipids in both groups. For all measurable rates to products in both liver and non-hepatic tissue diabetes caused no reduction, but the associated rate constants and clearance constants were invariably impaired. Rates to non-hepatic products exceeded those to hepatic, save for glycogen in diabetics, however as ratios to recipient mass the hepatic rates were higher. An observed high rate to hepatic glycogen in diabetics accompanying a high glycogen content points to a relative depression of phosphorylase and/or activation of synthetase by hyperglycemia. It also argues against the presence of an on–off mechanism which would direct movement either to synthesis alone or degradation alone.

An in vitro bioassay for a mulluscan gonadotropin

1975 ◽  
Vol 62 (2) ◽  
pp. 433-446
Author(s):  
M. J. Wells ◽  
R. K. O'Dor ◽  
S. K. Buckley
Keyword(s):  
Protein Synthesis ◽  
High Rate ◽  
Follicle Cells ◽  
Octopus Vulgaris ◽  
Amino Acid Incorporation ◽  
Gland Extract ◽  
Acid Incorporation ◽  
Kinetics Of

1. Protein synthesis occurs at a high rate in the ovaries of maturing Octopus vulgaris and can be measured from the incorporation of [14C]leucine in vivo and in isolated groups of eggs in vitro. 2. Removal of the optic glands in vivo 1--3 days prior to testing markedly reduces amino acid incorporation in vivo or in vitro. After 5 days in vivo incorporation stops. 3. The rate of incorporation in vitro is increased by the addition of optic gland extract. 4. Analysis of the kinetics of leucine uptake and incorporation in vitro indicates that the hormone has an effect on the inward transport of leucine which is independent of its action on protein synthesis. 5. Electron-microscope studies of the follicle cells and ova show that the former are the site of protein synthesis. 6. Changes in either uptake or incorporation into protein by the follicle cells can be used as a qualitative biolobical assay for the optic gland hormone. Uptake is very easy to measure but incorporation is the more sensitive parameter. Either is potentially suitable as a quantitative assay for this and perhaps also for other molluscan gonadotropins.

Evaluation of hepatic glycogen content, some haematological and biochemical parameters of alloxan-induced diabetic rats treated with combinations of glibenclamide and G. latifolium extract

2017 ◽  
Vol 14 (4) ◽  
Author(s):  
Patrick E. Aba
Keyword(s):  
Glycogen Content ◽  
Diabetic Rats ◽  
Hepatic Glycogen ◽  
Control Groups ◽  
Group 4 ◽  
Male Wistar Rats ◽  
The Mean ◽  
Group 2 ◽  
Alloxan Monohydrate ◽  
Group 1

AbstractBackgroundDiabetes is associated with both biochemical and haematological complications. Combination therapy has been advocated to mitigate some of these complications.AimThis study was designed to investigate the effects of glibenclamide andMethodsThirty male Wistar rats were assigned into five groups of six rats each. Groups 2–5 rats received intraperitoneally, 160 mg/kg of alloxan monohydrate while group 1 rats served as normal control. Groups 2–5 rats were respectively treated with 10 mL/kg distilled water (DW), 2 mg/kg glibenclamide, 200 mg/kg GL and 2 mg/kg glibenclamide and 200 mg/kg GL, while group 1 rats received 10 mL/kg DW. All treatments wereResultsCreatinine and BUN values of groups 3 and 4 rats were comparable to that of group 1 but were significantly (p<0.05) lower when compared with those of groups 2 and 5. There were significant (p<0.05) increases in the mean hepatic glycogen content, RBC, PCV, and Hb of group 4 rats when compared to those of group 2.ConclusionsIt was concluded that a combination of glibenclamide and

Effect of stress on hepatic 11β-hydroxysteroid dehydrogenase activity and its influence on carbohydrate metabolism

2006 ◽  
Vol 84 (10) ◽  
pp. 977-984 ◽  
Author(s):  
María Eugenia Altuna ◽  
Sandra Marcela Lelli ◽  
Leonor C. San Martín de Viale ◽  
María Cristina Damasco
Keyword(s):  
Phosphoenolpyruvate Carboxykinase ◽  
Hydroxysteroid Dehydrogenase ◽  
Tissue Level ◽  
Hepatic Glycogen ◽  
New Approach ◽  
The Metabolic Syndrome ◽  
Gluconeogenic Enzyme ◽  
Glycogen Deposition ◽  
Kinetics Of

Stress activates the synthesis and secretion of catecholamines and adrenal glucocorticoids, increasing their circulating levels. In vivo, hepatic 11β-hydroxysteroid dehydrogenase 1 (HSD1) stimulates the shift of 11-dehydrocorticosterone to corticosterone, enhancing active glucocorticoids at tissue level. We studied the effect of 3 types of stress, 1 induced by bucogastric overload with 200 mmol/L HCl causing metabolic acidosis (HCl), the second induced by bucogastric overload with 0.45% NaCl (NaCl), and the third induced by simulated overload (cannula), on the kinetics of hepatic HSD1 of rats and their influence on the activity of the gluconeogenic enzyme phosphoenolpyruvate carboxykinase, glycemia, and glycogen deposition. Compared with unstressed controls, all types of stress significantly increased HSD1 activity (146% cannula, 130% NaCl, and 253% HCl), phosphoenolpyruvate carboxykinase activity (51% cannula, 48% NaCl, and 86% HCl), and glycemia (29% cannula, 30% NaCl, and 41% HCl), but decreased hepatic glycogen (68% cannula, 68% NaCl, and 78% HCl). Owing to these results, we suggest the following events occur when stress is induced: an increase in hepatic HSD1 activity, augmented active glucocorticoid levels, increased gluconeogenesis, and glycemia. Also involved are the multiple events indirectly related to glucocorticoids, which lead to the depletion of hepatic glycogen deposits, thereby contributing to increased glycemia. This new approach shows that stress increments the activity of hepatic HSD1 and suggests that this enzyme could be involved in the development of the Metabolic Syndrome.

Rate of Incorporation of CO2 Carbon into Glucose and Other Body Constituents in Vivo

1975 ◽  
Vol 53 (5) ◽  
pp. 895-902 ◽  
Author(s):  
R. A. Shipley ◽  
A. P. Gibbons
Keyword(s):  
Fasting Glucose ◽  
Specific Activity ◽  
Fold Increase ◽  
Whole Body ◽  
Appreciable Amount ◽  
Hepatic Glycogen ◽  
Total Lipids ◽  
Fourfold Increase ◽  
Glucose Carbon

Specific activity curves of respired CO2 and of body glucose after intravenous NaH14CO3 as tracer and, in separate experiments, after [U-14C]glucose as tracer were employed to assess rate of interchange of carbon between HCO3 and glucose, and to calculate other rates of input and output for each of these substances. Solution for six rates attending the model was by integrals rather than by curve analysis. Fasting caused a twofold increase in rate of transport of CO2 carbon to glucose. Whereas in fed animals this rate was only 7% of the forward flow from glucose to CO2, it rose to 31% during fasting. Glucose carbon derived from CO2 rose from 3.7 to 20%. As expected, the rates of entry of new glucose to blood, and the conversion rate of glucose to products in body depots and to CO2 were reduced by fasting, whereas, the non-glucose input to CO2 was increased. Fasting was attended by a 20-fold increase in rate of conversion of CO2-derived carbon to hepatic glycogen and a fourfold increase to non-hepatic glycogen. Protein exceeded all whole-body depots for rate of acceptance of such carbon, and total lipids received an appreciable amount, but fasting caused no overall increase for either.

scholarly journals Age-related augmentation of phosphorylase b kinase in hepatic tissue from the glycogen-storage-disease (gsd/gsd) rat

1986 ◽  
Vol 238 (3) ◽  
pp. 811-816 ◽  
Author(s):  
D G Clark ◽  
S D Neville ◽  
M Brinkman ◽  
P V Nelson ◽  
R J Illman ◽  
...  
Keyword(s):  
Food Deprivation ◽  
Glycogen Content ◽  
Storage Disease ◽  
Liver Weight ◽  
Liver Glycogen ◽  
Glycogen Storage ◽  
Hepatic Tissue ◽  
Blood Metabolites ◽  
Hepatic Glycogen ◽  
Age Related

The effects of food deprivation on body weight, liver weight, hepatic glycogen content, glycogenolytic enzymes and blood metabolites were compared in young and old phosphorylase b kinase-deficient (gsd/gsd) rats. Although the concentration of glycogen in liver from 9-week-old female gsd/gsd rats (730 mumol of glucose equivalents/g wet wt.) was increased by 7-8% during starvation, total hepatic glycogen was decreased by 12% after 24 h without food. In 12-month-old male gsd/gsd rats the concentration of liver glycogen (585 mumol of glucose equiv./g wet wt.) was decreased by 16% and total hepatic glycogen by nearly 40% after food deprivation for 24 h. Phosphorylase b kinase and phosphorylase a were present at approx. 10% of the control activities in 9-week-old gsd/gsd rats, but both enzyme activities were increased more than 3-fold in 12-month-old affected rodents. It is concluded that the age-related ability to mobilize hepatic glycogen appears to result from the augmentation of phosphorylase b kinase during maturation of the gsd/gsd rat.

scholarly journals 3-Mercaptopicolinic acid, an inhibitor of gluconeogenesis

1974 ◽  
Vol 138 (3) ◽  
pp. 387-394 ◽  
Author(s):  
N. W. DiTullio ◽  
C. E. Berkoff ◽  
B. Blank ◽  
V. Kostos ◽  
E. J. Stack ◽  
...  
Keyword(s):  
Rat Kidney ◽  
Diabetic Rats ◽  
Kidney Cortex ◽  
Hepatic Glycogen ◽  
Hypoglycaemic Effect ◽  
Rat Kidney Cortex ◽  
Urea Production ◽  
Rat Livers

1. 3-Mercaptopicolinic acid (SK&F 34288) inhibited gluconeogenesis in vitro, with lactate as substrate, in rat kidney-cortex and liver slices. 2. In perfused rat livers, gluconeogenesis was inhibited when lactate, pyruvate or alanine served as substrate, but not with fructose, suggesting pyruvate carboxylase or phosphoenolpyruvate carboxylase as the site of inhibition. No significant effects were evident in O2 consumption, hepatic glycogen, urea production, or [lactate]/[pyruvate] ratios. 3. A hypoglycaemic effect was evident in vivo in starved and alloxan-diabetic rats, starved guinea pigs and starved mice, but not in 4h-post-absorptive rats. 4. In the starved rat the hypoglycaemia was accompanied by an increase in blood lactate. 5. A trace dose of [14C]lactate in vivo was initially oxidized to a lesser extent in inhibitor-treated rats, but during 90min the total CO2 evolved was slightly greater. The total amount of the tracer oxidized was not significantly different from that in the controls.

scholarly journals Glycogen synthesis in the perfused liver of streptozotocin-diabetic rats

1975 ◽  
Vol 150 (2) ◽  
pp. 153-165 ◽  
Author(s):  
P D Whitton ◽  
D A Hems
Keyword(s):  
Direct Action ◽  
Glycogen Synthesis ◽  
Diabetic Rats ◽  
Hepatic Glycogen ◽  
Perfused Liver ◽  
Glycogen Accumulation ◽  
Glycogen Synthetase ◽  
Streptozotocin Diabetic Rats

1. Net glycogen accumulation was measured in sequentially removed samples during perfusion of the liver of starved streptozotocin-diabetic rats, and shown to be significantly impaired, compared with rates in normal (starved) rats. 2. In perfusions of normal livers with glucose plus C3 substrates, there was an increase in the proportion of glycogen synthetase ‘a’, compared with that in the absence of substrates. This response to substrates, followed in sequential synthesis and enzymic sensitivity in the perfused liver of diabetic rats were reversed by pretreatment in vivo with glucose plus fructose, or insulin. Glucose alone did not produce this effect. 4. Glucose, fructose, insulin or cortisol added to e perfusion medium (in the absence of pretreatment in vivo) did not stimulate glycogen synthesis in diabetic rats. 5. In intact diabetic rats, there was a decline in rates of net hepatic glycogen accumulation, and the response of glycogen synthetase to substrates. The most rapid rates of synthesis were obtained after fructose administration. 6. These results demonstrate that there is a marked inherent impairment in hepatic glycogen synthesis in starved diabetic rats, which can be rapidly reversed in vivo but no in perfusion. Thus hepatic glycogen synthesis does not appear to be sensitive to either the short-term direct action of insulin (added alone to perfusions) of to long-term insulin deprivation in vivo. The regulatory roles of substrates, insulin and glycogen synthetase in hepatic glycogen accumulation are discussed.

Induction of hepatic glycogenesis in the fetal rat

1989 ◽  
Vol 256 (1) ◽  
pp. E49-E54 ◽  
Author(s):  
P. A. Gruppuso ◽  
D. L. Brautigan
Keyword(s):  
Phosphatase Activity ◽  
Protein Phosphatase ◽  
Glycogen Content ◽  
Glycogen Synthase ◽  
Hepatic Glycogen ◽  
Phosphatase Activities ◽  
Protein Phosphatase Type 1 ◽  
Protein Phosphatase Type

We have performed an in vivo study to test the hypothesis that induction of fetal hepatic glycogenesis is stimulated by insulin and involves activation of protein phosphatase type-1. Control animals and the following two experimental groups were studied: maternal fasting for 48 h prior to term and chronic maternal hyperinsulinemia for 5 days prior to term. Maternal fasting led to decreased fetal hepatic glycogen content and fetal growth retardation. In contrast, no decrease in fetal hepatic glycogen content or fetal weight occurred with maternal hyperinsulinemia despite fetal hypoglycemia and fetal hypoinsulinemia. In neither model were fetal hepatic synthase phosphatase or phosphorylase phosphatase activities affected. In control fetuses, the appearance of hepatic glycogen from days 17 to 21 of gestation correlated with induction of glycogen synthase. Phosphorylase phosphatase and synthase phosphatase activities already were present on day 17 of gestation and changed little through term. However, phosphatase catalytic protein reactive with anti-phosphatase type-1 antibodies did increase approximately fivefold from day 18 to 21. In adult animals fasted for 48 h, 50% of hepatic glycogen synthase phosphatase activity was lost, whereas phosphorylase phosphatase activity was stimulated fourfold. The apparent size of protein phosphatase type-1 catalytic subunit as detected by Western immunoblotting was altered by fasting in the adult but not by substrate restriction (maternal fasting) in the fetus.(ABSTRACT TRUNCATED AT 250 WORDS)

Antihyperglycemic Activity of Aqueous Extract of Euphorbia guyoniana in Streptozotocin-Induced Diabetic Rats

2021 ◽  
Vol 21 ◽  
Author(s):  
Ayoub Amssayef ◽  
Bouchra Azzaoui ◽  
Ismail Bouadid ◽  
Mohamed Eddouks
Keyword(s):  
Oral Administration ◽  
Aqueous Extract ◽  
Extensor Digitorum Longus ◽  
Glycogen Content ◽  
Diabetic Rats ◽  
Extensor Digitorum ◽  
Histopathological Analysis ◽  
Glycogen Depletion ◽  
Traditional Use

Aims: This work assessed the antihyperglycemic effect of Euphorbia guyoniana. Background: Euphorbia guyoniana (Boss. and Reut.) is widely used in traditional medicine. Objective: This study was designed to confirm this traditional use by assessing its antihyperglycemic capacity in vivo. Methods: The effect of the aqueous extract of Euphorbia guyoniana (Boss. and Reut.) (60 mg/kg) on glycemia in both normal and diabetic rats was evaluated. The glycogen content in the liver and skeletal muscles (extensor digitorum longus and soleus) was measured. Furthermore, liver histopathological analysis was performed. Results: The findings showed that Euphorbia guyoniana (Boss. and Reut.) exhibited a significant decrease in glycaemia in diabetic rats (from 20±2 mmol/l to 5.5 mmol/l after 6 hours of oral administration; p<0.0001 and from 20±2 mmol/l to 4.5 mmol/l after 7 days of once-daily repeated oral administration of the aqueous Euphorbia guyoniana extract; p<0.0001). In addition, the extract increased the glycogen content in the liver (41±4 mg/g versus 70±5 mg/g in normal and diabetic rats respectively) and extensor digitorum longus (39±4 mg/g versus 60±1 mg/g in normal and diabetic rats, respectively), and partially restored corporal weight in diabetic rats. Furthermore, this aqueous extract has been shown to suppress hyperglycemia induced by glucose load in treated diabetic rats. Additionally, hepatic histology in diabetic rats has been improved. This plant revealed the presence of several phytochemical constituents and possessed antioxidant activity. Conclusion: The current study evidenced that Euphorbia guyoniana (Boss. and Reut.) has a beneficial effect on improving hyperglycemia and glycogen depletion in the diabetic state.

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