356 ROLE OF GPR30-ADENYLYL CYCLASE (AC)-PKA PATHWAY IN ESTRADIOL 17β-GLUCURONIDE (E17G) INDUCED CHOLESTASIS IN ISOLATED RAT HEPATOCYTES COUPLETS (IRHC) AND ISOLATED PERFUSED RAT LIVER (IPRL)

In perfused rat liver a decrease of cytosol pH, determined with pH-sensitive microelectrodes7 from 7.2 to 6.85 is associated with a 50% fall in ureogenesis from ammonium chloride. In isolated rat hepatocytes the fall in ureogenesis due to acidosis is associated with decrease in the mitochondrial and cytosolic concentration of citrulline. Limitation of carbamoyl phosphate synthesis and thus citrulline supply could be responsible for the inhibition of ureogenesis observed.

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The effects of glucose and of potassium ions on the interconversion of the two forms of glycogen phosphorylase and of glycogen synthetase in isolated rat liver preparations

Biochemical Journal ◽

10.1042/bj1520105 ◽

1975 ◽

Vol 152 (1) ◽

pp. 105-114 ◽

Cited By ~ 256

Author(s):

L Hue ◽

F Bontemps ◽

H Hers

Keyword(s):

Rat Liver ◽

Glucose Concentration ◽

Glycogen Phosphorylase ◽

Rat Hepatocytes ◽

Isolated Perfused Rat Liver ◽

Isolated Rat Hepatocytes ◽

Glycogen Synthetase ◽

Sequence Of Events ◽

Lag Period ◽

Isolated Rat

1. In the isolated perfused rat liver, increasing glucose concentration from 5.5 to 55 mm in the perfusion medium caused a sequential inactivation of glycogen phosphorylase and activation of glycogen synthetase. The latter change was preceded by a lag period which corresponded to the time required to inactivate the major part of the phosphorylase. 2. The same sequence of events was observed in isolated rat hepatocytes incubated at 37°C. In this preparation, the rate of phosphorylase inactivation was greatly increased by increasing the concentration of glucose and/or of K+ ions in the external medium. The same agents also caused the activation of glycogen synthetase, but this effect was secondary to the inactivation of phosphorylase. 3. In both types of preparations, the rate of synthetase activation was modulated by the residual amount of phosphorylase a that remained after the initial phase of rapid inactivation and was independent of glucose concentration. 4. In isolated hepatocytes, the rate of conversion of glucose into glycogen was propotional to the activity of synthetase a in the preparation. This conversion was preceded by a lag period which could be shortened by increasing either glucose or K+ concentration in the medium. The incorporation of labelled glucose into glycogen was simultaneous with a glycogenolytic process which could not be attributed to the activity of phosphorylase a.

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Biosynthesis of Guanidine in Isolated Rat Hepatocytes, Perfused Rat Liver and Intact Animals

Nephron ◽

10.1159/000187989 ◽

1994 ◽

Vol 67 (3) ◽

pp. 334-339 ◽

Cited By ~ 1

Author(s):

Katsumi Takemura ◽

Sohji Nagase ◽

Kazumasa Aoyagi ◽

Michihiro Gotoh ◽

Akio Koyama ◽

...

Keyword(s):

Rat Liver ◽

Rat Hepatocytes ◽

Perfused Rat Liver ◽

Isolated Rat Hepatocytes ◽

Isolated Rat

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A Comparison of Plasminogen Activators Derived from Rat Plasma, Primary Rat Hepatocytes and Isolated Perfused Rat Liver

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657155 ◽

1982 ◽

Vol 47 (02) ◽

pp. 166-172 ◽

Cited By ~ 4

Author(s):

Yoav Sharoni ◽

Maria C Topal ◽

Patricia R Tuttle ◽

Henry Berger

Keyword(s):

Rat Liver ◽

Isoelectric Point ◽

Rat Hepatocytes ◽

Cell Types ◽

Plasminogen Activators ◽

Rat Plasma ◽

Isolated Perfused Rat Liver ◽

Perfused Rat Liver ◽

Molecular Weights ◽

Physiological Relevance

SummaryOf the two cell types it was possible to culture from the dissociated rat liver, hepatocytes and Kupffer cells, only the former were fibrinolytically active. Rat hepatocytes during the first 24 hr in culture secreted two plasminogen activators with molecular weights identical to those found in rat plasma, an 80,000-dalton form (PA-80) and a 45,000-dalton form (PA-45). Partially purified preparations of plasminogen activators from both sources were subjected to isoelectric focusing (IEF) to compare characteristics further. There were three distinct peaks of PA-45 in each preparation with isoelectric points of 7.1, 7.2 and 7.4; all electrophoretic forms had the same low affinity to fibrin. PA-80 from both sources displayed similar IEF profiles with forms ranging from pH values of 7 to 8, all with the same high affinity to fibrin. The major form of PA-80 in the plasma preparation had an isoelectric point of 7.9 whereas that in the hepatocyte preparation had an isoelectric point of 7.6. The isolated perfused rat liver was also shown to produce both PA-80 and PA-45 emphasizing the physiological relevance of the findings with hepatocytes. It is concluded that in the rat hepatocytes contribute to the plasma profile with regard to the plasminogen activator content.

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