• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.11a
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• pp.135-140
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• 1994

Over past decades, numerous in vitro model has been developed to investigate drug metabolism. In the order of complexity we found the isolated perfused liver, hepatocytes in co-culture with epithelial cells, hepatocytes in suspension and in primary culture and subcellular hepatic microsomal fractions. Because they can be easily prepared from both animals (pharmacological and toxicological species) and humans (whole livers as well as biopsies obtained during surgery) hepatocytes in primary culture provide the most powerful model to better elucidate drug behavior at an early stage of preclinical development such as : 1. the characterization of main biotransformation reactions. 2. the identification of phase I and phase II isozymes involved in such reactions 3. the evaluation of interspecies differences allowing the selection of a second toxicological animal species more closely related to man on the basis of metabolic profiles 4. the detection of the inducing and/or inhibitory effects of a drug on metabolic enzymes, the prediction of drug interactions 5. the estimation of inter-individual variability in biotransformation reactions. The use of hepatocytes, and in particular those obstained from humans, at an early stage of drug development allows the obtention of more predictive preclinical data and a better knowledge of drug behavior in humans before the first administration of the drug in healthy volunteers.

• Korean Journal of Pharmacognosy
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• v.21 no.1
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• pp.92-99
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• 1990

Effects of the methanol extract of Bupleuri Radix on primary cultured chicken embryonic brain cells, dorsal root ganglia (DRG) and rat hepatocytes were studied. The methanol extract of Bupleuri Radix at the concentration ranging from $10{\;}{\mu}g/ml\;to\;100{\;}{\mu}g/ml$ significantly recovered the cytotoxicity of rat hepatocytes induced by the treatment of galactosamine; at the concentration of $100\;{\mu}g/ml$, values of GOT and GPT in the culture medium were reduced by the 60% and 75%, respectively of those in the absence of the methanol extract of Bupleuri Radix. The addition of the methanol extract of Bupleuri Radix. into chicken embryonic brain cells which were cultured with a deficient medium significantly increased the number of cells promoting the neurite outgrowth. However, the methanol extract of Bupleuri Radix showed no effect on the activities of PDHC and acetylcholinesterase in primary cultured brain cells.

• Toxicological Research
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• v.3 no.2
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• pp.73-80
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• 1987

Primary cultures of adult rat hepatocytes were used to study the cytotoxicity of D-galactosamine. Hepatocytes were isolated by a collagenase perfusion technique and maintained as monolayers in serum-free medium on collagen-coated culture dishes. Treatment of galactosamine to the culture markedly inhibited the uptake of ${\alpha}$-aminoisobutyric acid (AIB) inducible with glucagon and dexamethasone. At0.1 mM of galactosamine, AIB uptake was inhibited significantly when treated for 12 hr. At higher doses (0.25, 0.5 and 1.0mM), a significant inhibition was noticed after 1 hr exposure. Generally the magnitude of the inhibition was related to the dose and treatment time of galactosamine. Treatment of galactosamine also produced a dose- and treatment time-related suppression of the tyrosine aminotransferase (TAT) induction caused by dexamethasone. Meanwhile, uptake of ouabain was not affected by the treatment of galactosamine. The viability of the hepatocytes was decreased only slightly by the treatment of galactosamine; more than 87% of the cells excluded tryphane blue when treated 1 mM galactosamine for 12 hr. Galactosamine induced depressions of AIB uptake and TAT activity were prevented by the simultaneous addition of uridine to the culture. D-Galactosamine, cytotoxicity, hepatocytes culture, ${\alpha}$-aminoisobutyric acid uptake, tyrosine aminotransferase.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.159-164
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• 2003

Effects of Al on vitellogenin (VTG) and VTG mRNA induction by estradiol-17 $\beta$($E_2$) were examined in primary hepatocyte culture of rainbow trout. Hepatocytes were precultured for 2 days and then E2 ($2{\times}10^{-6}$M) and Al ($10^{-6}-10^{-4}$M) were simultaneously added to the incubation medium. Hepatocytes were cultured for 5 more days. Media and hepatocytes were then analyzed by SDS-PAGE and Northern blotting for VTG and VTG mRNA, respectively. These metal had no appreciable effect on the viability of hepatocytes in culture. However, Al interfered with VTG production and VTG mRNA expression. Al reduced VTG production in a concentration-dependent way and a significant reduction accurred at Al concentrations greater than $5{\times}10^{-5}$M. VTG mRNA expression also decreased with a negative correlation with Al concentration (r＝-0.98). These results suggest that Al inhibit VTG production at the transcriptional level to reduce VTG mRNA expression.

• Toxicological Research
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• v.2 no.1
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• pp.1-7
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• 1986

Procarcinogen induced DNA single-strand breaks and unschduled DNA synthesis were measured in primary rat hepatocytes culture. For DNA single-strand breaks assay, rat liver DNA was prelabeled by injection 3H-thymidine during the peak of DNA synthesis following partial hepatectomy. Hepatocytes were isolated from the rat 2 weeks after surgery by a collagenase perfusion techinique and maintained as monolayers in serum free medium on collagen-coated culture dishes. DNA sigle-strand breaks were measured by the alkaline elution techinique.

• Biomolecules & Therapeutics
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• v.12 no.3
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• pp.185-188
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• 2004

The purpose of this study is to evaluate the effect of cigarette smoke condensate (CSC) on toxification/detoxification metabolic pathway in primary cultured rat hepatocytes. We measured the activities of cytochrome P450 monooxygenases (CYP450s) and UDP-glucuronyltransferase, sulfotransferase and glutathione-S-transferase in CSC-treated rat hepatocytes. CSC significantly increased the activities of hepatic CYP4501A1 and CYP4501A2 to 7.5 fold and 1.6 fold respectively, compared with control level. However, CSC did not affect the activities of conjugation enzymes. We a1so examined if treatment of CSC could change thc cytotoxicity of acetaminophen (AA) through modulation of metabolizing enzymes. In rat hepatocytes, pretreatment with CSC potentiated the cytotoxicity of AA. This result indicates that potentiation of AA toxicity by CSC pretreatment may be related to induction of CYP4501A1 and CYP4501A2.

• Toxicological Research
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• v.5 no.1
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• pp.9-15
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• 1989

The effect of butylated hydroxytoluene (BHT) and its major metabolite, 3, 5-di-tert-butyl-4-hydroxybenzoic acid (BHT-acid) on the uptake of taurocholate into hepatocytes was studied using the primary culture of rat hepatocytes. Hepatocyte were isolated by an in situ collagenase perfusion technique and maintained as a monolayer in serum-free meadia for 24 hours before use. The uptake of taurocholate was saturable with an apparent Km of 12.8+2.8 MuM and Vmax of 0.18+0.01 nmol/mg/min. Both BHT and BHT-acid inhibited the hepatocellular uptake of taurocholate when they were added to the culture.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.718-722
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• 1998

Scopoletin (7-hydroxy-6-methoxycoumarin), a coumarin, was isolated from the aerial part of Solanum lyratum Thunb. by the activity-guided fractionation employing carbon te trachloride-intoxicated primary cultured rat hepatocytes as a screening system. Its hepatoprotective activity was first evaluated by measuring the release of glutamic pyruvic transaminase and sorbitol dehydrogenase from carbon tetrachloride-intoxicated rat hepatocytes into the culture medium. Scopoletin significantly reduced the releases of glutamic pyruvic transaminase and sorbitol dehydrogenase from the carbon tetrachloride-intoxicated primary cultured rat hepatocytes by 53% and 58%, respectively, from the toxicity in a dose-dependent manner over concentration ranges of 1mcM to 50mcM. Further studies revealed that at the concentration of 10mcM, scopoletin significantly preserved glutathione content by 50% and the activity of superoxide dismutase by 36% and also inhibited the production of malondialdehyde to the degree as seen in the control.

• Toxicological Research
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• v.15 no.1
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• pp.89-93
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• 1999

2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) is known to induce cytochrome p450 1A1 and to activate c-Src kinase and p21 Ras. This study examined the molecular interactions of adaptor proteins including Shc, Grb2, and Sos in rat primary hepatocytes and their relationship to the induction of CYP1A1 by TCDD. TCDD induced CYP1A1 level and EROD activity in a dose-dependent mode. Sos/Grb2 association isincreased by TCDDㅑㅜ a dose dependent mode. Tyrosine phosphorylated Shc, mainly p152, onloads to Grb2/Sos complex upon TCDD stimulation. The electrophoretic mobility shift of Sos is showed by TCDD. These results indicate that TCDD modulated the molecular interaction features of adaptor compoes proteins including Shc, Grb2, and Cnl in early signaling pathway of TCDD-mediated CYP 1A1 induction of rat primary hepatocyte.

• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.209-213
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• 2000

The cultured mycelia of Ganoderma lucidum were extracted and the extract was separated into six fractions by organic solvent fractionation. The antihepatotoxic activity of all the fractions was evaluated by measuring activities of glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT). Among the fractions tested, the high-polarity fractions such as aqueous and n-butanol fractions significantly reduced activities of GPT and GOT in CCl4- and galactosamine-intoxicated rat primary hepatocytes. When intracellular synthetic activities were measured by pulsing the rate primary cultured hepatocytes with [3H]-uridine and [3H]-leucine, activities of DNA, RNA and protein. When direct toxicities of the fractions were measured against human hepatoma(SK-Hep-1), the non-polarity fractions such as n-butanol and ethyl acetate fractions showed potent direct cytotoxicities even at the concentration of 1 $\mu\textrm{g}$/ml. These data showed that Ganoderma lucidum has hepatoprotective and hepatotoxic recovery principles in its mycelia.