scholarly journals An in vitro demonstration of peroxisome proliferation and increase in peroxisomal β-oxidation system mRNAs in cultured rat hepatocytes treated with ciprofibrate

FEBS Letters ◽  
1989 ◽  
Vol 250 (2) ◽  
pp. 205-210 ◽  
Author(s):  
Shobha Thangada ◽  
Keith Alvares ◽  
Mario Mangino ◽  
Mohammed I. Usman ◽  
M.Sambasiva Rao ◽  
...  
Keyword(s):  
Rat Hepatocytes ◽  
Peroxisome Proliferation ◽  
Cultured Rat Hepatocytes ◽  
Oxidation System

The Use of Primary Cultured Rat Hepatocytes for the Assessment of Xenobiotic Effects on Biotransformation

1991 ◽  
Vol 19 (2) ◽  
pp. 209-213
Author(s):  
Gabi Schepers ◽  
Christiane Aschmann ◽  
Sabine Mörchel
Keyword(s):  
Cell Viability ◽  
Rat Hepatocytes ◽  
Standard Test ◽  
In Vitro Test ◽  
Chlorinated Phenols ◽  
Test Protocol ◽  
Primary Cultured Rat Hepatocytes ◽  
Cultured Rat Hepatocytes ◽  
Different Response

An in vitro test protocol is reported, which, using primary cultured rat hepatocytes, allows for the screening of xenobiotic effects on biotransformation as well as on basal cellular functions. O-Deethylation of 7-ethoxycoumarin (7-EC) and subsequent conjugation of the metabolite 7-hydroxycoumarin (7-HC) with sulphate or glucuronic acid are determined, as representative parameters for the hepatic biotransformation. Cell viability is examined by measuring cellular ATP content and leakage of lactate dehydrogenase. With respect to immediate and delayed effects on biotransformation reactions, the standard test protocol includes exposure to xenobiotics for 1, 24 and 48 hours. Different response patterns could be demonstrated for the solvents dimethylformamide (DMF) and dimethylsulphoxide (DMSO), and the chlorinated phenols, pentachlorophenol (PCP) and hexachlorophene (HCP), which are known to uncouple mitochondrial respiration. Short-term incubation with the solvents resulted in decreased 7-EC- O-deethylation without signs of cytotoxicity. PCP and HCP inhibited 7-EC- O-deethylation and 7-HC-conjugation, affecting sulphate and glucuronide formation differently. 24-hour exposures to PCP and HCP resulted in decreased 7-ethoxycoumarin- O-deethylase activity, which correlated with diminished cell viability, while DMSO and DMF enhanced 7-EC- O-deethylation at sub-cytotoxic concentrations. After exposure for 48 hours to the solvents, enzyme induction was even more pronounced.

An In Vitro Assay to Assess Transporter-Based Cholestatic Hepatotoxicity Using Sandwich-Cultured Rat Hepatocytes

2009 ◽  
Vol 38 (2) ◽  
pp. 276-280 ◽  
Author(s):  
John H. Ansede ◽  
William R. Smith ◽  
Cassandra H. Perry ◽  
Robert L. St. Claire ◽  
Kenneth R. Brouwer
Keyword(s):  
Rat Hepatocytes ◽  
In Vitro Assay ◽  
Vitro Assay ◽  
Cultured Rat Hepatocytes

scholarly journals The effect of glucose on the potency of two distinct glycogen phosphorylase inhibitors

2002 ◽  
Vol 367 (2) ◽  
pp. 443-450 ◽  
Author(s):  
Birgitte ANDERSEN ◽  
Niels WESTERGAARD
Keyword(s):  
Synergistic Effect ◽  
Glycogen Phosphorylase ◽  
Rat Hepatocytes ◽  
Rabbit Muscle ◽  
Ic50 Value ◽  
Cultured Rat Hepatocytes ◽  
Effect Of Glucose ◽  
Glycogen Phosphorylase Inhibitors ◽  
Glucose Analogue

Two distinct glycogen phosphorylase inhibitors, 5-chloro-1H-indole-2-carboxylic acid [1-(4-fluorobenzyl)-2-(4-hydroxy-piperidin-1-yl)-2-oxoethyl]amide (CP-320,626) and 1,4-dideoxy-1,4-d-arabinitol (DAB), were characterized in vitro with respect to the influence of glucose on their potencies. CP-320,626 has previously been shown to bind to a newly characterized indole site, whereas DAB seems to act as a glucose analogue, but with slightly different properties from those of glucose. When analysed in pig liver glycogen phosphorylase a (GPa) activity assays, the two inhibitors showed very different properties. When GPa activity was measured in the physiological direction (glycogenolysis), DAB was the most potent inhibitor with an IC50 value of 740±9nM compared with the IC50 value for CP-320-626 of 2.39±0.37μM. There was no effect of glucose on the inhibitory properties of DAB, whereas a glucose analogue N-acetyl-β-d-glucopyranosylamine (1-GlcNAc) antagonized the effect of DAB. Likewise, there was no synergistic effect of CP-320,626 and glucose, whereas CP-320,626 and 1-GlcNAc inhibited GPa in synergy. Moreover, the synergistic effect of glucose and CP-320,626 was GPa-isoform-specific, since CP-320,626 and glucose inhibited rabbit muscle GPa in synergy when the GPa activity was measured towards glycogenolysis. When GPa activity was measured towards glycogen synthesis, CP-320,626 showed a synergistic effect with glucose, whereas the effect of DAB was slightly antagonized by glucose in this assay direction. Caffeine was included in the investigation as a control GP inhibitor, and both glucose and 1-GlcNAc potentiated the effect of caffeine independent of the assay direction. In primary cultured rat hepatocytes 1-GlcNAc and CP-320,626 inhibited basal and glucagon-induced glycogenolysis in synergy, whereas the ability of DAB to inhibit basal or glucagon-induced glycogenolysis was unaltered by 1-GlcNAc. Glucose had no effect on either CP-320,626 or DAB inhibition of glycogenolysis in cultured rat hepatocytes. In conclusion, the present study shows that the two GP inhibitors are kinetically very distinct and neither of the inhibitors demonstrates a physiologically relevant glucose dependence in vitro.

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