Causes of the zonal distribution of glycogen in the liver acinus after a fat-rich diet. I. Glycogen deposition in the acini of rat livers during ?normal? ?reversed? perfusion

1972 ◽  
Vol 173 (3) ◽  
pp. 325-331 ◽  
Author(s):  
W. Den Otter ◽  
G. Tuit
Keyword(s):  
Zonal Distribution ◽  
Liver Acinus ◽  
Glycogen Deposition ◽  
Rat Livers

Causes of zonal distribution of glycogen in the liver acinus after a fat-rich diet

1973 ◽  
Vol 29 (5) ◽  
pp. 545-546 ◽  
Author(s):  
W. den Otter ◽  
L. F. Blikkendaal-Lieftinck ◽  
J. W. Koten
Keyword(s):  
Zonal Distribution ◽  
Liver Acinus

scholarly journals Quantitative histochemical analysis of glucose-6-phosphatase activity in rat liver using an optimized cerium-diaminobenzidine method.

1990 ◽  
Vol 38 (10) ◽  
pp. 1413-1419 ◽  
Author(s):  
G N Jonges ◽  
C J Van Noorden ◽  
R Gossrau
Keyword(s):  
Oxidative Polymerization ◽  
Male Rats ◽  
Functional Difference ◽  
Histochemical Analysis ◽  
Zonal Distribution ◽  
Cerium Phosphate ◽  
Liver Acinus ◽  
G6pase Activity ◽  
Km Value ◽  
Cytophotometric Analysis

We have optimized a cerium-diaminobenzidine-based method for histochemical analysis of glucose-6-phosphatase (G6Pase) activity and have determined quantitative data on the zonal distribution pattern in the liver acinus of fasted male rats. In the cerium-diaminobenzidine technique, cerium instead of lead ions is used as capturing reagent for the enzymatically liberated phosphate. For light microscopy, the primary reaction product, cerium phosphate, is then visualized by conversion into cerium perhydroxide using hydrogen peroxide and subsequent oxidative polymerization of diaminobenzidine to diaminobenzidine brown as the final reaction product. Variation of the substrate (glucose-6-phosphate) concentration in the incubation medium yielded in periportal zones a KM value of 2.3 +/- 0.7 mM and a Vmax value of 0.96 +/- 0.18 (expressed as mean integrated absorbance). In perivenous zones a KM value of 1.1 +/- 0.4 mM and a Vmax value of 0.51 +/- 0.08 were calculated. The cytophotometric analysis performed in this study demonstrated for the first time that a functional difference of G6Pase, the key enzyme for gluconeogenesis, exists in the periportal and perivenous zones of the liver acinus. Periportal zones contain twice as many enzyme molecules (high Vmax) as perivenous zones, but the affinity for the substrate is twice as low. This may have important implications for the concept of metabolic zonation of the liver and also for glucose homeostasis in the blood.

Albumin influences sulfobromophthalein transport by hepatocytes of each acinar zone

1984 ◽  
Vol 246 (1) ◽  
pp. G86-G95 ◽  
Author(s):  
D. L. Gumucio ◽  
J. J. Gumucio ◽  
J. A. Wilson ◽  
C. Cutter ◽  
M. Krauss ◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Steady State ◽  
Relative Concentration ◽  
Biliary Secretion ◽  
Homogeneous Distribution ◽  
Single Pass ◽  
Liver Acinus ◽  
Cellular Concentration ◽  
Direct Demonstration ◽  
Rat Livers

To determine whether profiles of decreasing concentration were generated among hepatocytes of the liver acinus during the transport of sulfobromophthalein sodium (BSP), rat livers were perfused with various concentrations of this dye (10 microM to 1 mM) in the presence and absence of albumin. After steady-state conditions for the biliary secretion of BSP had been attained, pieces of liver were rapidly frozen. Following the alkalinization of cryostat-cut sections, the relative concentration of BSP in hepatocytes of each zone and the effect of albumin on this localization were quantitated by microspectrophotometry. The results showed that BSP, perfused in the absence of albumin, was efficiently extracted by the liver (95% on a single pass), generating distinct profiles of decreasing cellular concentration from zone 1 to zone 3 at every concentration of BSP. However, the addition of albumin to the perfusate greatly reduced the extraction of BSP from the sinusoidal compartment and resulted in the abolition of the differences in BSP content between hepatocytes of zone 1 and zone 3. These results represent a direct demonstration that, as predicted by mathematical modeling, binding of BSP to albumin indeed results in a more homogeneous distribution of BSP within the liver acinus. A simple and direct microspectrophotometric method is therefore available to follow the changes in the relative concentration of BSP among the hepatocytes of the various acinar zones.

Ultrastructural changes in isolated rat liver perfused with cyclic heptapeptide toxins from norwegian freshwater cyanobacteria (blue-green algae)

1987 ◽  
Vol 45 ◽  
pp. 858-859
Author(s):  
A.S. Dabholkar ◽  
W.W. Carmichael ◽  
K. Berg ◽  
J. Wyman
Keyword(s):  
Ultrastructural Changes ◽  
Sprague Dawley ◽  
Isolated Rat Liver ◽  
Blue Green Algae ◽  
Sprague Dawley Rats ◽  
Cyclic Heptapeptide ◽  
Intracellular Changes ◽  
Oscillatoria Agardhii ◽  
Rat Livers ◽  
Isolated Rat

Intracellular changes in the hepatocytes of isolated rat livers perfused with cyclic heptapeptide toxins are described. The toxins used are 1) -Ala-Leu- β-methyl isoAsp-Arg-ADDA-isoGlu-mdha (M.W. 944) from Microcystis aeruginosa- Lake Akersvatn, Norway; 2) -Ala-Arg-isoAsp-Arg-ADDA-isoGlu-mdha (M.W. 1023) from Oscillatoria agardhii var. - Lake Kolbatnvatn, Norway; 3) -Ala-Arg-isoAsp-Arg-ADDA-isoGlu-dha (M.W. 1009) from Oscillatoria agardhii var. isothrix - Lake Froylandsvatn, Norway. Approximate LD intraperitoneal mouse for the toxins is 50, 500 and 1000 μg/kg respectively.Livers were removed from male Sprague Dawley rats and perfused for 15 min with a blood-free perfusate (50 ml) followed by 60 min with perfusate containing i) 25, 50, or 200 μg of M. aeruginosa toxin ii) 50, 250, 500 or 1000 μg of O. agardhii var. toxin and iii) 1000, 2000, 2500 or 5000 μg of O. agardhii var. isothrix toxin. Control livers were perfused for 75 min with the blood-free perfusate.

The Anticancer Drug Ellipticine is an Inducer of Rat NAD(P)H:Quinone Oxidoreductase

2007 ◽  
Vol 72 (10) ◽  
pp. 1350-1364 ◽  
Author(s):  
Marie Stiborová ◽  
Helena Dračínská ◽  
Dagmar Aimová ◽  
Petr Hodek ◽  
Jiří Hudeček ◽  
...  
Keyword(s):  
Polymerase Chain Reaction ◽  
Enzymatic Activity ◽  
Wistar Rats ◽  
Antineoplastic Agent ◽  
Chain Reaction ◽  
Potent Inducer ◽  
Male Wistar Rats ◽  
Polymerase Chain ◽  
Dt Diaphorase ◽  
Rat Livers

The antineoplastic agent ellipticine was investigated for its ability to induce the biotransformation enzyme NAD(P)H:quinone oxidoreductase (DT-diaphorase, EC 1.6.99.2) in male Wistar rats. Using the real-time polymerase chain reaction, the levels of NAD(P)H:quinone oxidoreductase mRNA were determined in livers, kidneys and lungs of rats treated intraperitoneally with ellipticine (40 mg/kg body weight) and of control (untreated) rats. Cytosolic fractions were isolated from the same tissues of control and ellipticine-treated rats and tested for NAD(P)H:quinone oxidoreductase protein expression and its enzymatic activity. The results demonstrate that ellipticine is a potent inducer of NAD(P)H:quinone oxidoreductase in rat livers and kidneys, while no induction of this enzyme was detectable in rat lungs. The increase in levels of NAD(P)H:quinone oxidoreductase mRNA correlates with the increase in expression of its protein and enzymatic activity, measured with menadione and 3-nitrobenzanthrone as substrates. The results, the identification of the potential of ellipticine to induce NAD(P)H:quinone oxidoreductase, suggest that this drug is capable of modulating biological efficiencies of the toxicants and/or drugs that are reductively metabolized by this enzyme.

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