THE EFFECT OF INSULIN ON THE DISTRIBUTION OF GLUCOSE BETWEEN THE BLOOD PLASMA AND THE LIVER IN ALLOXAN-DIABETIC AND ADRENALECTOMIZED RATS

1963 ◽  
Vol 41 (12) ◽  
pp. 2431-2439 ◽  
Author(s):  
G. Hetenyi Jr. ◽  
F. K. Kopstick ◽  
L. J. Retelstorf
Keyword(s):  
Cell Membrane ◽  
Blood Plasma ◽  
Liver Cell ◽  
Liver Glycogen ◽  
Liver Cells ◽  
Diabetic Rats ◽  
Hepatic Cell ◽  
Very High ◽  
Adrenalectomized Rats

In diabetic rats the concentration of glucose in the liver was less than in the plasma. The relative accumulation of glucose in the liver cell after the injection of insulin was also found to be significantly less in previously untreated diabetic than in normal rats. Pretreatment with insulin restored the response to normal. Experiments with labeled glucose indicated that the rate at which glucose is carried through the hepatic cell membrane is very high compared to the rate at which glucose is being formed in the liver cells in diabetic rats. The relatively small amount of glucose accumulating after insulin in livers of diabetic rats originates from the plasma. In adrenalectomized rats which have very little liver glycogen, the relative accumulation of glucose in liver cells, following the injection of insulin, was less than that in normals. These experiments indicate that in normal rats a large part of the glucose retained in the liver after the injection of insulin originates from non-labeled endogenous hepatic sources, presumably glycogen.

THE EFFECT OF INSULIN ON THE DISTRIBUTION OF GLUCOSE BETWEEN THE BLOOD PLASMA AND THE LIVER IN ALLOXAN-DIABETIC AND ADRENALECTOMIZED RATS

1963 ◽  
Vol 41 (1) ◽  
pp. 2431-2439 ◽  
Author(s):  
G. Hetenyi Jr. ◽  
F. K. Kopstick ◽  
L. J. Retelstorf
Keyword(s):  
Cell Membrane ◽  
Blood Plasma ◽  
Liver Cell ◽  
Liver Glycogen ◽  
Liver Cells ◽  
Diabetic Rats ◽  
Hepatic Cell ◽  
Very High ◽  
Adrenalectomized Rats

In diabetic rats the concentration of glucose in the liver was less than in the plasma. The relative accumulation of glucose in the liver cell after the injection of insulin was also found to be significantly less in previously untreated diabetic than in normal rats. Pretreatment with insulin restored the response to normal. Experiments with labeled glucose indicated that the rate at which glucose is carried through the hepatic cell membrane is very high compared to the rate at which glucose is being formed in the liver cells in diabetic rats. The relatively small amount of glucose accumulating after insulin in livers of diabetic rats originates from the plasma. In adrenalectomized rats which have very little liver glycogen, the relative accumulation of glucose in liver cells, following the injection of insulin, was less than that in normals. These experiments indicate that in normal rats a large part of the glucose retained in the liver after the injection of insulin originates from non-labeled endogenous hepatic sources, presumably glycogen.

scholarly journals The metabolism of l-phenylalanine and l-tyrosine by liver cells isolated from adrenalectomized rats and from streptozotocin-diabetic rats

1985 ◽  
Vol 228 (1) ◽  
pp. 249-255 ◽  
Author(s):  
J C Stanley ◽  
M J Fisher ◽  
C I Pogson
Keyword(s):  
Insulin Treatment ◽  
Maximal Activity ◽  
Liver Cells ◽  
Diabetic Rats ◽  
Steroid Treatment ◽  
Phosphorylation State ◽  
Tyrosine Metabolism ◽  
Streptozotocin Diabetic Rats ◽  
Adrenalectomized Rats

Flux through, and maximal activities of, key enzymes of phenylalanine and tyrosine degradation were measured in liver cells prepared from adrenalectomized rats and from streptozotocin-diabetic rats. Adrenalectomy decreased the phenylalanine hydroxylase flux/activity ratio; this was restored by steroid treatment in vivo. Changes in the phosphorylation state of the hydroxylase may mediate these effects; there was no significant change in the maximal activity of the hydroxylase. Tyrosine metabolism was enhanced by adrenalectomy; this was not related to any change in maximal activity of the aminotransferase. Steroid treatment increased the maximal activity of the aminotransferase. Both acute (3 days) and chronic (10 days) diabetes were associated with increased metabolism of phenylalanine; insulin treatment in vivo did not reverse these changes. Although elevated hydroxylase protein concentration was a major factor, changes in the enzyme phosphorylation state may contribute to differences in phenylalanine degradation in the acute and chronic diabetic states. Tyrosine metabolism, increased by diabetes, was partially restored to normal by insulin treatment in vivo. These changes can, to a large extent, be interpreted in terms of changes in the maximal activity of the aminotransferase.

Adrenal, Hypophyseal and Pancreatic Hormones in the Liver Glycogen Response to Low Atmospheric Pressure

1957 ◽  
Vol 191 (2) ◽  
pp. 342-344
Author(s):  
L. L. Langley ◽  
C. H. Gunthorpe
Keyword(s):  
Atmospheric Pressure ◽  
Liver Glycogen ◽  
Diabetic Rats ◽  
Pancreatic Hormones ◽  
Minimal Dose ◽  
Significant Difference ◽  
Hypophysectomized Rats ◽  
Low Atmospheric Pressure ◽  
Glycogen Deposition ◽  
Adrenalectomized Rats

The administration of 3 cc of adrenocortical extract (Upjohn) to adrenalectomized rats fasted at sea-level fails to cause liver glycogen deposition. Such animals under low atmospheric pressure accumulate about 1% liver glycogen. Adrenalectomized-hypophysectomized rats maintained on a minimal dose of hypophyseal extract, given 3 cc of adrenocortical extract and stressed do not deposit liver glycogen. These results suggest that the hypophyseal hormones function not only to control the adrenal cortices under these conditions, but also may contribute directly to the observed carbohydrate alterations. When larger doses of hypophyseal hormones are used there is a significant difference in liver glycogen between the stressed and nonstressed groups indicating the possible implication of still another agent, perhaps insulin, since alloxan diabetic rats do not accumulate liver glycogen in response to low atmospheric pressure.

scholarly journals The role of tryptophan 2,3-dioxygenase in the hormonal control of tryptophan metabolism in isolated rat liver cells. Effects of glucocorticoids and experimental diabetes

1985 ◽  
Vol 229 (2) ◽  
pp. 499-504 ◽  
Author(s):  
M Salter ◽  
C I Pogson
Keyword(s):  
Fold Increase ◽  
Maximal Activity ◽  
Kynurenine Pathway ◽  
Liver Cells ◽  
Diabetic Rats ◽  
Hormonal Control ◽  
Acetyl Coa ◽  
Dexamethasone Phosphate ◽  
Adrenalectomized Rats

The metabolism of L-tryptophan by isolated liver cells prepared from control, adrenalectomized, glucocorticoid-treated, acute-diabetic, chronic-diabetic and insulin-treated chronic-diabetic rats was studied. Liver cells from adrenalectomized rats metabolized tryptophan at rates comparable with the minimum diurnal rates of controls, but different from rates determined for cells from control rats 4h later. Administration of dexamethasone phosphate increased the activity of tryptophan 2,3-dioxygenase (EC 1.13.11.11) 7-8-fold, and the flux through the kynurenine pathway 3-4-fold, in cells from both control and adrenalectomized rats. Increases in flux through kynureninase (EC 3.7.1.3) and to acetyl-CoA can be explained in terms of increased substrate supply from tryptophan 2,3-dioxygenase. The metabolism of tryptophan was increased 3-fold in liver cells isolated from acutely (3 days) diabetic rats, with a 7-8-fold increase in the maximal activity of tryptophan 2,3-dioxygenase. The oxidation of tryptophan to CO2 and metabolites of the glutarate pathway increased 4-5-fold, consistent with an increase in picolinate carboxylase (EC 4.1.1.45) activity. Liver cells isolated from chronic (10 days) diabetic rats metabolized tryptophan at rates comparable with those of cells from acutely diabetic rats, but with a 50% decrease in the activity of tryptophan 2,3-dioxygenase. The proportion of flux from tryptophan 2,3-dioxygenase to acetyl-CoA, however, was increased by 50%; this was indicative of further increases in the activity of picolinate carboxylase. Administration of insulin partially reversed the effects of chronic diabetes on the activity of tryptophan 2,3-dioxygenase and flux through the kynurenine pathway, but had no effect on the increased activity of picolinate carboxylase. The role of tryptophan 2,3-dioxygenase in regulating the blood tryptophan concentration is discussed with reference to its sensitivity to the above conditions.

Factors Determining the Liver Glycogenating Action of Orinase

1958 ◽  
Vol 192 (3) ◽  
pp. 514-516 ◽  
Author(s):  
W. L. Henry ◽  
John H. Kim ◽  
Alice S. Hall
Keyword(s):  
Beta Cell ◽  
Liver Glycogen ◽  
Diabetic Animal ◽  
Diabetic Rats ◽  
Diabetic Rat ◽  
Protamine Zinc Insulin ◽  
Series Of Experiments ◽  
Adrenalectomized Rats

The liver glycogenating action of Orinase was studied in normal, adrenalectomized and alloxan diabetic rats. The adrenalectomized rats were studied in three groups, salt maintained, cortisone maintained and cortisone plus adrenaline maintained. The alloxan diabetic rats were studied in two groups, protamine zinc insulin (P.Z.I.) maintained and uncontrolled. Of the adrenalectomized rats only those maintained on cortisone plus adrenaline responded to Orinase administration with increased liver glycogen. The alloxan diabetic animal maintained on P.Z.I. presented increased liver glycogen after Orinase administration but the untreated alloxan diabetic rat did not. This series of experiments indicated that the liver glycogenating effect seen during Orinase administration requires the participation of adrenomedullary, adrenocortical and beta cell hormones.

scholarly journals TRANSFORMATION OF A HISTOCOMPATIBILITY IMMUNOGEN INTO A TOLEROGEN

1973 ◽  
Vol 138 (3) ◽  
pp. 723-733 ◽  
Author(s):  
Stephen H. Nimelstein ◽  
Allan R. Hotti ◽  
Halsted R. Holman
Keyword(s):  
Structural Change ◽  
Cell Membrane ◽  
Spleen Cell ◽  
Liver Cell ◽  
Cellular Response ◽  
Cell Membranes ◽  
Humoral Response ◽  
Cellular Responses ◽  
Liver Cells ◽  
Liver Cell Membrane

H-2 antigens on spleen cell membranes absorb antibody to H-2 antigens and induce both humoral and cellular responses. Liver cell membrane H-2 antigens by contrast also absorb antibody but do not influence cellular response and are tolerogenic for the humoral response. This paper demonstrates that syngeneic liver cells contain a substance which can transform the properties of allogeneic spleen cell membranes into those of allogeneic liver cell membranes, i.e., transform a humoral immunogen into a humoral tolerogen. The process appears to be accompanied by cleavage of an antigen component from the spleen membrane and hence to result in a structural change in the H-2 antigen.

scholarly journals The metabolism of l-tryptophan by liver cells prepared from adrenalectomized and streptozotocin-diabetic rats

1981 ◽  
Vol 200 (3) ◽  
pp. 605-609 ◽  
Author(s):  
S A Smith ◽  
C I Pogson
Keyword(s):  
Kynurenine Pathway ◽  
Liver Cells ◽  
Diabetic Rats ◽  
Insulin Deficiency ◽  
Cell Preparation ◽  
Metabolic Fate ◽  
Carboxylase Activity ◽  
Streptozotocin Diabetic Rats ◽  
Adrenalectomized Rats

1. The metabolism of L-tryptophan by liver cells prepared from fed normal, adrenalectomized and streptozotocin-diabetic rats was studied. 2. At physiological concentrations (0.1 mM), the rate of oxidation of tryptophan by tryptophan 2,3-dioxygenase was 3-fold greater in liver cells from diabetic rats than in those from fed rats. In liver cells from diabetic rats, oxidation of tryptophan to CO2 and metabolites of the glutarate pathway was increased 7-fold. Quinolinate synthesis was decreased by 50%. These findings are consistent with an increase in picolinate carboxylase activity. 3. Rates of metabolism of 0.1 mM-tryptophan by hepatocytes from fed and adrenalectomized rats were similar. 4. In all three types of cell preparation, fluxes through tryptophan 2,3-dioxygenase with 2.5 mM-tryptophan were 7-fold greater than those obtained with 0.1 mM-tryptophan. Tryptophan 2,3-dioxygenase and kynureninase fluxes in hepatocytes from fed and adrenalectomized rats were comparable, whereas those in liver cells from diabetic rats were increased 2.5-fold and 3.3-fold respectively. Picolinate carboxylase activities of liver cells from diabetic rats were 15-fold greater than those of cells from fed rats, but rates of quinolinate synthesis were unchanged. 5. It is concluded that: (i) adrenal corticosteroids are not required for the maintenance of basal activities of the kynurenine pathway, whereas (ii) chronic insulin deficiency produces changes in both the rate of oxidation and metabolic fate of tryptophan carbon.

scholarly journals Permeability of the liver cell membrane to quinolinate

1977 ◽  
Vol 164 (1) ◽  
pp. 283-286 ◽  
Author(s):  
K R F Elliott ◽  
C I Pogson ◽  
S A Smith
Keyword(s):  
Steady State ◽  
Cell Membrane ◽  
Guinea Pig ◽  
Liver Cell ◽  
Liver Cells ◽  
Pig Liver ◽  
Liver Cell Membrane ◽  
Guinea Pig Liver

Quinolinate was taken up by both rat and guinea-pig liver cells. Equilibrium was reached after approx. 20 min with rat cells, but guinea-pig cells had not achieved a steady state after 60 min. There was no evidence to suggest that quinolinate is rapidly metabolized by either species. The concentrations of quinolinate attained in rat and guinea-pig cells after short periods of incubation with 0.5 mM-quinolinate did not inhibit gluconeogenesis. These results raise further doubts as to the mechanism of quinolinate action in liver.

Metabolism of 2-C14-pyruvate after adrenalectomy

1960 ◽  
Vol 199 (6) ◽  
pp. 1059-1063
Author(s):  
W. W. Winternitz ◽  
W. G. Forrest
Keyword(s):  
Blood Plasma ◽  
Liver Glycogen ◽  
Carbohydrate Utilization ◽  
Highly Active ◽  
Tissue Homogenates ◽  
Adrenalectomized Rats

Normal and adrenalectomized rats were infused with 2 C14-pyruvate for 90 minutes. The carcasses and livers were then analyzed for glycogen, protein and fat. The radioactivity of whole tissue homogenates was also assayed. Normal rats formed a large amount of highly active liver glycogen; the adrenalectomized animals did not. The discrepancy was not accounted for by accumulation of C14 in any of the fractions or organs studied, although slightly increased amounts were found in the expired CO2 and in the blood plasma. It is suggested that increased carbohydrate utilization after adrenalectomy may be secondary to diminished glycogenesis and may occur over all available routes.

Effects of Hypophysectomy on the Fine Structure of Rat Liver Cells

1967 ◽  
Vol 25 ◽  
pp. 156-157
Author(s):  
Robert R. Cardell
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Rat Liver ◽  
Liver Cell ◽  
Anterior Pituitary ◽  
Liver Cells ◽  
Biochemical Studies ◽  
Liver Functions ◽  
Rat Liver Cells ◽  
And Control

Hypophysectomy of the rat renders this animal deficient in the hormones of the anterior pituitary gland, thus causing many primary and secondary hormonal effects on basic liver functions. Biochemical studies of these alterations in the rat liver cell are quite extensive; however, relatively few morphological observations on such cells have been recorded. Because the available biochemical information was derived mostly from disrupted and fractionated liver cells, it seemed desirable to examine the problem with the techniques of electron microscopy in order to see what changes are apparent in the intact liver cell after hypophysectomy. Accordingly, liver cells from rats which had been hypophysectomized 5-120 days before sacrifice were studied. Sham-operated rats served as controls and both hypophysectomized and control rats were fasted 15 hours before sacrifice.

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