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Schimke RT. Control of enzyme levels in mammalian tissues. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 37:135-87. [PMID: 4570065 DOI: 10.1002/9780470122822.ch3] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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2
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Ramakrishnan R, DuBois DC, Almon RR, Pyszczynski NA, Jusko WJ. Pharmacodynamics and pharmacogenomics of methylprednisolone during 7-day infusions in rats. J Pharmacol Exp Ther 2002; 300:245-56. [PMID: 11752123 DOI: 10.1124/jpet.300.1.245] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
An array of adverse steroid effects was examined on a whole body, tissue, and molecular level. Groups of male adrenalectomized Wistar rats were subcutaneously implanted with Alzet mini-pumps giving zero-order release rates of 0, 0.1, and 0.3 mg/kg/h methylprednisolone for 7 days. The rats were sacrificed at various times during the 7-day infusion period. A two-compartment model with a zero order input could adequately describe the kinetics of methylprednisolone upon infusion. Blood lymphocyte counts dropped to a minimum by 6 h and were well characterized by the cell trafficking model. The time course of changes in body and organ (liver, spleen, thymus, gastrocnemius muscle, and lungs) weights was described using indirect response models. Markers of gene-mediated steroid effects included hepatic cytosolic free receptor density, receptor mRNA, tyrosine aminotransferase (TAT) mRNA, and TAT levels. Our fifth-generation model of acute corticosteroid pharmacodynamics was used to predict the time course of receptor/gene-mediated effects. An excellent agreement between the expected and observed receptor dynamics suggested that receptor events and mRNA autoregulation are not altered upon 7-day methylprednisolone dosing. However, the model indicated a decoupling between the receptor and TAT dynamics with this infusion. The strong tolerance seen in TAT mRNA induction could be partly accounted for by receptor down-regulation. An amplification of translation of TAT mRNA to TAT and/or a reduction in the enzyme degradation rate could account for the observed exaggerated TAT activity. Our results exemplify the importance of biological signal transduction variables in controlling receptor/gene-mediated steroid responses during chronic dosing.
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Affiliation(s)
- Rohini Ramakrishnan
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, State University of New York at Buffalo, 14260, USA
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3
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Messina JL, Chatterjee AK, Strapko HT, Weinstock RS. Short- and long-term effects of insulin on tyrosine aminotransferase gene expression. Arch Biochem Biophys 1992; 298:56-62. [PMID: 1355958 DOI: 10.1016/0003-9861(92)90093-c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In the present study the relationship between changes in tyrosine aminotransferase (TAT) enzyme activity, cytoplasmic mRNA levels, and gene transcription in response to both short- and long-term exposure to insulin was investigated. Insulin acutely inhibited transcription of the TAT gene by 50% in serum-deprived rat H4 hepatoma cells. Following this initial 50% decrease in transcription, there was a 2.5-fold induction in TAT activity that could not be accounted for by a concomitant increase in TAT mRNA levels. Insulin had no effect on the half-life of TAT mRNA. Insulin exposure for short periods of time also inhibited the glucocorticoid- and cAMP-induced transcription of the TAT gene. Like insulin, protein synthesis inhibitors acutely inhibited basal and glucocorticoid-induced TAT transcription. TAT activity gradually returned toward basal levels after 8 h of insulin treatment. A second insulin-induced increase in TAT activity (3.5-fold above basal levels) was observed by 24 h of insulin treatment. This second phase of insulin-induced TAT activity was associated with elevated levels of TAT transcription and TAT mRNA levels, and therefore, unlike the earlier stimulation, could be accounted for by changes in gene expression. Thus, the insulin-mediated regulation of the TAT gene in H4 cells is complex. Different transcriptional and post-transcriptional mechanisms are likely to be involved in the biphasic responses to insulin.
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Affiliation(s)
- J L Messina
- Department of Physiology, SUNY Health Science Center, Syracuse 13210
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4
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Yagi K, Suenobu N, Serada M, Tsuda K, Kondoh A, Miura Y. Stimulative effect of non-parenchymal liver cells on ability of tyrosine aminotransferase induction in hepatocytes. Cytotechnology 1992; 10:25-31. [PMID: 1369495 DOI: 10.1007/bf00376097] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Hepatocytes and non-parenchymal liver cells were isolated from adult rat liver and co-cultured for 48 hours as a monolayer on polystyrene culture dishes. The ability of tyrosine aminotransferase (TAT) induction in hepatocytes was examined in the presence of dexamethasone and dibutyryl cAMP. Non-parenchymal cells greatly enhance the ability of TAT induction of hepatocytes. A soluble factor with molecular weight of more than 10,000 is responsible for this enhancement, because conditioned medium prepared from non-parenchymal cells is also stimulatory. Non-parenchymal cells restored the ability in hepatocytes damaged with the addition of D-galactosamine. Conditioned medium prepared from non-parenchymal cells treated with D-galactosamine had higher activity of enhancement than the medium from normal cells. The soluble factor might be released in response to some signal of injury. Hepatocytes and non-parenchymal cells were immobilized within Ca-alginate, and although immobilized hepatocytes rapidly lost the ability to induce TAT, hepatocytes co-immobilized with non-parenchymal cells maintained the ability during 4 days of culture. These results indicated that non-parenchymal liver cells, as well as hepatocytes, could be used to construct a bioartificial liver support system.
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Affiliation(s)
- K Yagi
- Faculty of Pharmaceutical Sciences, Osaka University, Japan
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Miyazaki M, Bai L, Taga H, Hirai H, Sato J, Namba M. Expression of liver-specific functions and secretion of a hepatocyte growth factor by a newly established rat hepatoma cell line growing in a chemically-defined serum-free medium. RESEARCH IN EXPERIMENTAL MEDICINE. ZEITSCHRIFT FUR DIE GESAMTE EXPERIMENTELLE MEDIZIN EINSCHLIESSLICH EXPERIMENTELLER CHIRURGIE 1991; 191:297-307. [PMID: 1836893 DOI: 10.1007/bf02576686] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A rat hepatoma cell line 3'-mRLh-2 was established from 3'-methyl-4-dimethylaminoazobenzene-induced hepatoma. Cells proliferated well in 5Fs-DM-160, a chemically-defined serum-free medium; population doubling time was 68.5 h, and modal chromosome number was 81 (21%). The cells were transplantable, and the transplanted tumors were histologically diagnosed as hepatocellular carcinoma. They were cytochemically positive for gamma-glutamyl transpeptidase. The cells possessed about 30% of tyrosine aminotransferase activity level in the rat liver, and showed 5.5 to 7.4-fold induction of this enzyme activity in response to dexamethasone. Also, the cells secreted alpha-fetoprotein, albumin, transferrin, alpha 1-acid glycoprotein, C-reactive protein, fibrinogen, complement component C3, and other five-serum proteins. Furthermore, the conditioned medium stimulated DNA synthesis in primary cultures of adult rat hepatocytes in a dose-dependent, saturable manner and in the absence of epidermal growth factor. These properties of the cell line 3'-mRLh-2 were compared with those of the popular rat hepatoma cell lines, such as H4-II-E-C3 from Reuber hepatoma H35 and HTC from Morris hepatoma 7288C.
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Affiliation(s)
- M Miyazaki
- Department of Pathology, Okayama University Medical School, Japan
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6
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Moore PS, Koontz JW. Insulin-mediated regulation of tyrosine aminotransferase in rat hepatoma cells: inhibition of transcription and inhibition of enzyme degradation. Arch Biochem Biophys 1989; 275:486-95. [PMID: 2574563 DOI: 10.1016/0003-9861(89)90395-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Insulin induces the enzyme tyrosine aminotransferase (TAT) in Reuber H-35 rat hepatoma cells. A clone of these cells (KRC-7) was used to study the relationship between changes in enzyme activity and hybridizable mRNA, and rates of transcription for TAT in response to insulin. Our results indicate that enzyme activity is inducible by insulin in the presence of an inhibitor of RNA synthesis, suggesting that insulin functions post-transcriptionally to increase enzyme activity. Unexpectedly, insulin causes a decrease in the level of hybridizable TAT mRNA. Glucocorticoids cause an increase in TAT mRNA and insulin inhibits this increase when added either subsequent to or simultaneous with the addition of this agonist. Transcriptional runoffs demonstrate that insulin inhibits transcription of TAT to account for the aforementioned decrease in hybridizable mRNA. To examine the possibility that a post-translational mechanism is responsible for the increase in TAT activity caused by insulin, the rate of degradation of TAT protein was measured using polyclonal antibody. These experiments indicate that the rate of degradation of TAT is decreased about twofold in the presence of insulin, which suggests that part of the observed increase in TAT activity is due to selective post-translational stabilization of TAT. Therefore, insulin regulates TAT in KRC-7 cells by both transcriptional and post-translational mechanisms, the latter being responsible for the increase in activity.
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MESH Headings
- Animals
- Cell Line
- Enzyme Induction
- Gene Expression Regulation, Enzymologic/drug effects
- Insulin/pharmacology
- Kinetics
- Liver Neoplasms, Experimental/enzymology
- Molecular Weight
- RNA, Messenger/drug effects
- RNA, Messenger/genetics
- RNA, Neoplasm/drug effects
- RNA, Neoplasm/genetics
- RNA, Neoplasm/isolation & purification
- Rats
- Transcription, Genetic/drug effects
- Tumor Cells, Cultured/drug effects
- Tumor Cells, Cultured/enzymology
- Tyrosine Transaminase/biosynthesis
- Tyrosine Transaminase/genetics
- Tyrosine Transaminase/metabolism
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Affiliation(s)
- P S Moore
- Department of Biochemistry, University of Tennessee, Knoxville 37996-0840
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Affiliation(s)
- Y Miura
- Department of Biochemical Engineering, Faculty of Pharmaceutical Sciences, Osaka University, Japan
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8
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Shapiro LE, Wagner N. Growth of H-35 rat hepatoma cells in unsupplemented serum-free media: effect of transferrin, insulin and cell density. IN VITRO CELLULAR & DEVELOPMENTAL BIOLOGY : JOURNAL OF THE TISSUE CULTURE ASSOCIATION 1988; 24:299-303. [PMID: 3284876 DOI: 10.1007/bf02628831] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Serum-free tissue culture medium consisting of a 1:1 mixture of Dulbecco's modified Eagle's medium (DMEM) and Ham's F12 medium is herein shown to support growth of Reuber H-35 cells over several days in culture. Cells were initially plated in serum containing DMEM medium for 3 h. After cell attachment, serum is removed and replaced with a serum-free 1:1 mixture of these two commercially available tissue culture media. The doubling time of cell growth in this unsupplemented serum-free medium was 46 h in lightly plated cultures over the first 5 d. The presence of transferrin (5 micrograms/ml) and insulin (3.3 nM) results in a cell doubling time of 17 h, which equaled the growth rate in medium containing 10% fetal bovine serum. In the absence of transferrin, growth rates in serum-free medium were correlated with the cell density of cultures. Conditioned medium from dense, serum-free cultures has growth-stimulating activity in recipient lightly plated cultures. This simple, serum-free culture medium will facilitate studies on the growth regulation of H-35 rat hepatoma cells.
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Affiliation(s)
- L E Shapiro
- Department of Medicine, Montefiore Medical Center, Bronx, New York
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9
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Straus D, Takemoto C. Insulin negatively regulates albumin mRNA at the transcriptional and post-transcriptional level in rat hepatoma cells. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)61603-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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10
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Miura Y, Akimoto T, Kanazawa H, Yagi K. Synthesis and secretion of protein by hepatocytes entrapped within calcium alginate. Artif Organs 1986; 10:460-5. [PMID: 2879525 DOI: 10.1111/j.1525-1594.1986.tb02604.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The ability of entrapped hepatocytes to secrete plasma proteins was examined for the purpose of developing a biological artificial liver. Hepatocytes were isolated from adult rat liver by perfusion with collagenase. Isolated hepatocytes were entrapped within calcium alginate. The entrapped cells induced tyrosine aminotransferase (TAT) in the presence of dexamethasone and dibutyryl-cyclic AMP and retained the ability to induce TAT for 7 days. Moreover, entrapped cells could synthesize and secrete a biologically active form of coagulation Factor II, prothrombin. Two plasma proteins, lecithin: cholesterol acyltransferase and cholinesterase, were also secreted into the medium. Thus, hepatocytes within calcium alginate showed liver-specific characteristics, and these activities were almost comparable with those of monolayer-cultured cells.
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11
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Tran-Thi TA, Phillips J, Falk H, Decker K. Toxicity of D-galactosamine for rat hepatocytes in monolayer culture. Exp Mol Pathol 1985; 42:89-116. [PMID: 2857129 DOI: 10.1016/0014-4800(85)90021-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Hepatocellular injury was induced by exposure of primary cultures of rat hepatocytes to 4 mM D-galactosamine. The cell damage was very similar to that seen in vivo and in the isolated perfused rat liver, both in biochemical and in structural terms. The severity of the lesions caused by D-galactosamine was dependent on the age of the culture being treated. Less severe damage was found with older cultures. Since the primary metabolic effects of D-galactosamine were age-independent, the reduction in cell damage seems to be due to progressive cell dedifferentiation. Dexamethasone (1 microM) suppressed the full development of the injury, while 1 microM triiodo-L-thyronine enhanced it. A protection of hepatocytes by alpha 2-macroglobulin against the effects of D-galactosamine could be observed neither in vivo nor in vitro. Direct cytotoxic effects of endotoxin from Salmonella minnesota R 595 could be demonstrated only on hepatocytes in the early phases of primary culture using rather high doses of the purified lipopolysaccharide. It is unlikely that they play a major role in the hepatocellular injury seen following endotoxinemia in vivo. Lowering of extracellular Ca2+ concentration and additions of calcium/calmodulin inhibitors did not prevent cell injury after treatment with D-galactosamine. The results suggest that cell death is not due to an increased influx of Ca2+ into the cells.
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12
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McIntyre WR, Samuels HH. Triamcinolone acetonide regulates glucocorticoid-receptor levels by decreasing the half-life of the activated nuclear-receptor form. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(18)89748-4] [Citation(s) in RCA: 76] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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13
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Chessebeuf M, Fischbach M, Padieu P. Time course study of L-tyrosine aminotransferase induction in rat liver cell lines. Cell Biol Toxicol 1984; 1:31-40. [PMID: 6152899 DOI: 10.1007/bf00125563] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The enhancement of L-tyrosine aminotransferase activity by dexamethasone, an exclusive function of the liver, was serially measured at different passages of eight rat liver epithelial cell lines initiated and continuously grown in either a serum-supplemented medium or a serum-free medium. The enzyme basal activity was found to be 5.4 +/- 1.8 mU for cell lines in serum and 6.8 +/- 3.4 mU for cell lines without serum. Under the influence of dexamethasone (10(-6) mol/l for 5 hours) this basal level could be increased up to 2.9 fold in the presence of serum and 2.5 fold in its absence when investigations were carried out at early passages. During the following subcultures the induction ratio gradually declined and scarcely any induction could be detected after the 15th passage for cells grown in serum and after the 25th passage for cell lines grown without serum.
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Affiliation(s)
- M Chessebeuf
- Laboratoire de Biochimie Médicale, Faculté de Médecine, Dijon, France
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14
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Potter VR, Evanson TR, Gayda DP, Gurr JA. Cultured hepatoma cells for the study of enzyme regulation: induction of ornithine decarboxylase by insulin and asparagine. IN VITRO 1984; 20:723-31. [PMID: 6389319 DOI: 10.1007/bf02618878] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The induction and decay of ornithine decarboxylase (ODC) by insulin and asparagine in cultures of H4-II-EC3 (H35) hepatoma cells was studied in a modified Waymouth medium in the presence of fetal bovine serum (FBS) and in serum-free media. The insulin response was enhanced by the presence of asparagine although the effect of asparagine was not so much on the initial increase as it was on a slowing of the decline after the maximum was reached at 6 to 8 h after the supplements were added together with fresh medium. In all cases the initial ODC activity was zero at zero time for addition of media and supplements, and, after reaching the maximum, activity declined to near zero by 24 h. Fetal bovine serum gave induction that followed a similar time course but was inferior to the combination of insulin plus asparagine and, in fact, FBS inhibited the latter response. Putrescine (the product formed from ornithine by ODC), at 10(-5) M, markedly inhibited the induction of ODC by insulin or FBS, but the inhibition was less when asparagine was present.
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15
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Groenewald JV, Terblanche SE, Oelofsen W. Tyrosine aminotransferase: characteristics and properties. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1984; 16:1-18. [PMID: 6141963 DOI: 10.1016/0020-711x(84)90045-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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16
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Koontz JW, Wicks WD. Stimulation of tyrosine aminotransferase degradation by methylthioinosine. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(17)43546-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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17
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Pretranslational control of tyrosine aminotransferase synthesis by 8-bromo-cyclic AMP in H-4 rat hepatoma cells. J Biol Chem 1983. [DOI: 10.1016/s0021-9258(17)43990-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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18
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Haggerty DF, Chiappelli F, Kern R, Scully S, Lynch M. Regulation by glucocorticoids of rat-liver phenylalanine hydroxylase in vivo. Biochem Biophys Res Commun 1983; 115:965-70. [PMID: 6626234 DOI: 10.1016/s0006-291x(83)80029-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Phenylalanine hydroxylase, a liver-associated enzyme, is induced markedly by glucocorticoids in two permanent rat-hepatoma cell lines. In order to gain evidence that this phenomenon also occurs in vivo, we examined the effect of adrenalectomy and/or hormone supplementation on the levels of phenylalanine hydroxylase in the livers of adult rats: glucocorticoid administration increases, and adrenal ablation reduces, the activity of the hepatic enzyme, and the diminution occurring in the latter instance is entirely prevented by concurrent hormone replacement. These results thus corroborate earlier findings from a single experiment and are consistent with the hypothesis that adrenal corticosteroid hormones participate in modulating phenylalanine-hydroxylase levels within the diploid hepatocyte.
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19
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Meyer RD, Preston SL, McMorris FA. Glycerol-3-phosphate dehydrogenase is induced by glucocorticoids in hepatocytes and hepatoma cells in vitro. J Cell Physiol 1983; 114:203-8. [PMID: 6296163 DOI: 10.1002/jcp.1041140209] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Previous studies have shown that cytosolic glycerol-3-phosphate dehydrogenase (GPDH; EC 1.1.1.8) can be induced by glucocorticoids in mammalian brain, mammary gland, and thymus, but it was thought that no induction occurred in liver. We report here that GPDH is induced by glucocorticoids in several lines of hepatoma cells and in rat hepatocytes cultured in vitro. When rat hepatoma cells of clone FU5AH were exposed to 3 microM hydrocortisone (HC) for 3 days, GPDH specific activity increased greater than sixfold over control. The rate and extent of induction were similar in exponentially growing and stationary-phase cultures of cells. Four other hepatoma cell lines were inducible to a lesser extent, and three lines were not inducible. GPDH was also induced by glucocorticoids in cultures of hepatocytes isolated from livers of 6-day-old rats. The enzyme was induced three-to fourfold by the synthetic glucocorticoid, dexamethasone, in the presence of 1 nM insulin, but the induction was not observed in the absence of insulin.
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20
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Hargrove JL, Granner DK. Explanation for the apparent inactivation of tyrosine aminotransferase in hepatoma cells by concanavalin A. Biochem Biophys Res Commun 1982; 106:1042-8. [PMID: 6126188 DOI: 10.1016/0006-291x(82)91816-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Haggerty DF, Spector EB, Lynch M, Kern R, Frank LB, Cederbaum SD. Regulation of glucocorticoids of arginase and argininosuccinate synthetase in cultured rat hepatoma cells. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(18)34913-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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22
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Snoek GT, Voorma HO, van Wijk R. Positive and negative cAMP-mediated control of tyrosine aminotransferase synthesis in Reuber H35 hepatoma cells. EUROPEAN JOURNAL OF BIOCHEMISTRY 1982; 123:217-22. [PMID: 6121706 DOI: 10.1111/j.1432-1033.1982.tb06519.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Induction of L-tyrosine:2-oxoglutarate aminotransferase (EC 2.6.1.5) by N6,O2'-dibutyryl-adenosine 3',5'-monophosphate (Bt2cAMP) in Reuber H35 hepatoma cells reaches a maximum value between 3-5 h after addition of Bt2cAMP and subsequently decreases in the continuous presence of Bt2cAMP. We have investigated the kinetics of the increase, i.e. induction, and the decrease, i.e. the repressed state, of the tyrosine-aminotransferase-synthesizing system under these conditions. Our experimental results are as follows. 1. The repressed state of the tyrosine-aminotransferase-synthesizing system is not caused by a decrease in the intracellular cAMP concentration. 2. The repressed state is inhibited by actinomycin D (while induction is not inhibited). 3. During the repressed state no effect of dexamethasone on tyrosine aminotransferase synthesis is found, while during induction Bt2cAMP and dexamethasone act synergistically. 4. Longer starvation of the cells in serum-free medium has no influence on the kinetics of the induction/repressed state curve. From these results we have concluded that the mechanism of the transition to the repressed state of the tyrosine-aminotransferase-synthesizing system is essentially different from the mechanism of deinduction which occurs after removal of the inducer. Moreover, the repressed state of the system is a phenomenon which is induced by Bt2cAMP separately from induction at a different level of protein synthesis.
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Abstract
Various lectins were found to induce tyrosine aminotransferase in H-35 rat hepatoma cells grown in monolayer culture. Wheat germ agglutinin gave a maximal induction of tyrosine aminotransferase 6 hours after its addition. The induction time course was similar to that elicited by insulin. Fourteen micrograms of wheat germ agglutinin per milliliter gave half-maximal enzyme induction and 50 micrograms per milliliter gave the maximal response. The induction of tyrosine aminotransferase by wheat germ agglutinin was additive with the induction by either dexamethasone or dibutyryl adenosine 3',5'-monophosphate, but was not additive with the tyrosine amino transferase induction by insulin. Wheat germ agglutinin also mimicked insulin in the inhibition of cellular protein degradation in the absence of serum. The insulin-like effects of lectins should be considered in lectin-mediated manipulations such as agglutination.
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Abstract
Tyrosine aminotransferase induction has been studied in hepatocytes from untreated, partially and fully glucocorticoid-induced rats: enzyme activities were initially 12.9 +/- 1.7 (n = 16), 41.4 +/- 3.2 (n = 6) and 117.9 +/- 10.5 (n = 7) munits/mg protein, respectively. Untreated or fully induced hepatocytes maintain initial levels, whereas partially induced hepatocytes increase their tyrosine aminotransferase activity even in the presence of actinomycin D. Fully induced hepatocytes possess a normal protein synthetizing machinery and the mechanisms to degrade selectively tyrosine aminotransferase. The effect of progesterone treatment is consistent with these cells retaining a high dexamethasone level. Glucagon induces tyrosine aminotransferase via its second messenger, cyclic AMP. This induction decreases dramatically with in vivo glucocorticoid treatment. Time courses and effects of inhibitors are consistent with these in vivo and in vitro treatments being alternative methods of inducing tyrosine aminotransferase by the same basic pretranslational step.
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25
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Snoek GT, Voorma HO, Van Wijk R. Further evidence for translational regulation of tyrosine aminotransferase synthesis by dibutyryl cyclic AMP in Reuber H35 hepatoma cells. BIOCHIMICA ET BIOPHYSICA ACTA 1981; 655:107-12. [PMID: 6114749 DOI: 10.1016/0005-2787(81)90073-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Cyclic AMP derivatives increase the rate of synthesis of tyrosine aminotransferase in Reuber H35 hepatoma cells. Various studies lend support to the hypothesis that cyclic AMP increases the synthesis of tyrosine aminotransferase by acting at a posttranscriptional site. The presence of a limited non-translatable pool of tyrosine aminotransferase mRNA prior to the formation of the translatable tyrosine aminotransferase mRNA implicates a possible site of action of cyclic AMP. We compared the capacity of N6,O2'-dibutyryl cyclic AMP to induce tyrosine aminotransferase synthesis when untranslatable tyrosine aminotransferase mRNA sequences are present or absent. The transition of a condition in which non-translatable tyrosine aminotransferase mRNA sequences were present to a condition in which they were absent was established by preinduction of Reuber H35 cells with dexamethasone, followed by addition of actinomycin D. In the time period thereafter, the amount of non-translatable mRNA decreased and 1.5-2 h after addition of actinomycin D, only translatable tyrosine aminotransferase mRNA was present. It can be seen that the induction of tyrosine aminotransferase synthesis by dibutyryl cyclic AMP follows the normal decrease of tyrosine aminotransferase mRNA. We present evidence that dibutyryl cyclic AMP in Reuber H35 hepatoma cells regulates tyrosine aminotransferase synthesis at a posttranscriptional site independent of the pool of non-translatable tyrosine aminotransferase mRNA sequences, but influencing the efficiency of translation of active tyrosine aminotransferase mRNA.
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Nakamura T, Noda C, Ichihara A. Two phase regulation of tyrosine aminotransferase activity by insulin in primary cultured hepatocytes of adult rats. Biochem Biophys Res Commun 1981; 99:775-80. [PMID: 6113829 DOI: 10.1016/0006-291x(81)91232-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Rifkin DB, Crowe RM. Studies on the control of plasminogen activator production by cultured human embryonic lung cells: requirements for inhibition by corticosteroids. J Cell Physiol 1980; 105:417-22. [PMID: 7193216 DOI: 10.1002/jcp.1041050305] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The ability of actinomycin D to interfere with the dexamethasone-mediated inhibition of plasminogen activator (PA) production by human-embryonic lung (HuEL) cells has been examined. The enzyme produced by HuEL cells in the presence of both dexamethasone and actinomycin D appears to be the product of de novo protein synthesis, as determined by the dependence of PA production on active protein synthesis and the net increase in total PA during the course of an experiment. Inhibition of RNA synthesis must be continuous to maintain PA production in the presence of dexamethasone, since reinitiation of RNA synthesis causes an immediate loss of PA activity in the cells. Cordycepin and alpha-amanitin also prevent dexamethasone-mediated inhibition of PA in HuEL cells, indicating that the RNA whose synthesis must be prevented is of the mRNA class. These experiments imply that PA production in HuEL cells may be under translational as well as transcriptional control.
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29
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Wicks WD, Leichtling BH, Wimalasena J, Koontz J. Regulation of cAMP metabolism and specific protein synthesis in Reuber Hepatoma cells. Ann N Y Acad Sci 1980; 349:195-209. [PMID: 6111972 DOI: 10.1111/j.1749-6632.1980.tb29526.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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30
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Horvat A. Stimulation of RNA synthesis in isolated nuclei by an insulin-induced factor in liver. Nature 1980; 286:906-8. [PMID: 6157993 DOI: 10.1038/286906a0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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31
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Nakamura T, Shinno H, Ichihara A. Insulin and glucagon as a new regulator system for tryptophan oxygenase activity demonstrated in primary cultured rat hepatocytes. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)43858-1] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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32
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Gurr JA, Potter VR. Independent induction of tyrosine aminotransferase activity by dexamethasone and glucagon in isolated rat liver parenchymal cells in suspension and in monolayer culture in serum-free media. Exp Cell Res 1980; 126:237-48. [PMID: 6102037 DOI: 10.1016/0014-4827(80)90490-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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34
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Pitot HC, Sirica AE. Methodology and utility of primary cultures of hepatocytes from experimental animals. Methods Cell Biol 1980; 21B:441-56. [PMID: 6997684 DOI: 10.1016/s0091-679x(08)60697-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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35
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Vickrey HM, Joseph RR, McCann DS. Continuous culture of normal adult mammalian hepatocytes exhibiting parenchymal functions. IN VITRO 1979; 15:120-7. [PMID: 37154 DOI: 10.1007/bf02618108] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Past in vitro studies of liver-cell functions have been performed on nonproliferating primary cells or serially propagated hepatic monolayers of neoplastic or fetal origin. We optimized conditions for the selective culture of adult rabbit and canine liver parenchymal cells and presently have four differentiated proliferating monolayer strains. At the 30th passage level these hepatic cultures still display the specific liver parenchymal functions of albumin and fibrinogen synthesis as well as tyrosine aminotransferase activity. Optimization of the conditions for hepatocyte culture was monitored by [3H]thymidine incorporation. Albumin and fibrinogen synthesis were measured by bioradioimmunoassay and tryosine transaminase activity by a modification of Diamondstone's assay. Albumin and fibrinogen synthesis were correlated with hepatocyte growth kinetics.
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36
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Barnett CA, Barnhorst M, Fooshee CM, Saneto RP. Selection of a dexamethasone-resistant H-4-IIE-C3 rat hepatoma tissue-culture line. IN VITRO 1979; 15:128-37. [PMID: 37155 DOI: 10.1007/bf02618109] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Exposure of H-4-IIE-C3 rat hepatoma cell cultures to the synthetic glucocorticoid, dexamethasone, results in an inhibition of cellular proliferation which is not the result of steroid-induced cytolysis. A significant decrease in both the rate of DNA synthesis and DNA content precedes a detectable effect on cell number. Continuous culture of H-IIE-C3 cells in medium containing 10(-5) M dexamethasone results in the selection of a steroid-resistant cell population that has the growth characteristics of unselected sensitive cultures and shows normal steroid induction of tryosine transaminase. Selection is a slow process requiring 24 to 36 months to obtain a phenotypically stable resistant cell line, and can be subdivided into three phases--a sensitive phase, adaptation and resistance. A comparison of the karyotypes of unselected and resistant cultures shows that the selection process enriches for a dexamethasone-resistant subpopulation.
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37
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Gelehrter TD. Syneristic and antagonistic effects of glucocorticoids on insulin action. MONOGRAPHS ON ENDOCRINOLOGY 1979; 12:583-91. [PMID: 40118 DOI: 10.1007/978-3-642-81265-1_32] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
HTC cells, an established line of rat hepatoma cells in tissue culture, provide a useful experimental model system for studying the interaction of glucocorticoids and insulin in the regulation of protein metabolism. The actions of insulin and glucocorticoids on amino acid transport and protein degradation are antagonistic in this cell line. In contrast, the actions of these two hormones are additive with regard to the induction of tyrosine aminotransferase. The addition of insulin to HTC cells previously incubated with dexamethasone causes a rapid further doubling in the cellular concentration of this enzyme. The properties of the induction by insulin differ in several respects from the induction by glucocorticoids. The former occurs immediately, without the characteristic lag observed during induction by steroids. Insulin induction of transaminase does not require concomitant RNA synthesis, and does not cause the accumulation of specific mRNA for this enzyme as do glucocorticoids. Using specific immunoprecipitation techniques, we have demonstrated that insulin stimulates a nonselective increase in the rate of total protein synthesis in HTC cells, and a selective decrease in the rate of degradation of tyrosine aminotransferase relative to total protein. Thus the induction of transaminase by insulin involves two distinct actions of the hormone, affecting both synthesis and degradation of protein.
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38
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39
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Samuels H, Klein D, Stanley F, Casanova J. Evidence for thyroid hormone-dependent and independent glucocorticoid actions in cultured cells. Studies on the induction of growth hormone and glutamine synthetase in GH1 cells and tyrosine aminotransferase in Reuber H-35 cells. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)34551-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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40
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Nickol J, Lee K, Kenney F. Changes in hepatic levels of tyrosine aminotransferase messenger RNA during induction by hydrocortisone. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)34791-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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41
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Leichtling BH, Koontz J, Su JL, Wagner K, Roper MD, Wimalasena J, Wicks WD. Glucocorticoid requirement for tyrosine aminotransferase induction by adenosine 3':5'-cyclic phosphate analogs in somatic cell hybrids. Arch Biochem Biophys 1978; 185:525-34. [PMID: 24418 DOI: 10.1016/0003-9861(78)90197-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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42
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Ernest M, Feigelson P. Increase in hepatic tyrosine aminotransferase mRNA during enzyme induction by N6,O2'-dibutyryl cyclic AMP. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)38203-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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43
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44
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Effect of concanavalin A on tyrosine aminotransferase in rat hepatoma tissue culture cells. Rapid reversible inactivation of soluble enzyme. J Biol Chem 1977. [DOI: 10.1016/s0021-9258(17)40518-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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45
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Bushnell DE. Inhibition by ultraviolet irradiation of the glucocorticoid induction of tyrosine aminotransferase in bromodeoxyuridine-treated H-35 hepatoma. Biochem Biophys Res Commun 1977; 74:92-9. [PMID: 13795 DOI: 10.1016/0006-291x(77)91379-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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46
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Mullen VT, Barnett CA. Banded karyotypes of H-4-IIE-C3 rat hepatoma cells grown in vitro. IN VITRO 1976; 12:658-64. [PMID: 188753 DOI: 10.1007/bf02797467] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mitotic cells from the H-4-IIE-C3 rat hepatoma tissue culture line showed a range of 45 to 53 chromosomes per cell with 75% of the cells displaying a chromosome mumber between 49 and 52. Analysis of Wright's-Giemsa banded karyotypes of 22 cells revealed considerable cell to cell variation. Twenty-one structurally abnormal chromosomes were identified in these cells; the origin of nine of the 21 chromosomes were identified in these cells; the origin of nine of the 21 chromosomes could be determined. Of the structurally abnormal chromosomes detected, only one (M-1) occurred with a sufficiently high frequency to be of general use as a marker for these cells. This marker appears to be a Robertsonian translocation involving chromosome number 2 and chromosome number 10.
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47
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Plagemann PG, Erbe J. Glucocorticoids--uptake by simple diffusion by cultured Reuber and Novikoff rat hepatoma cells. Biochem Pharmacol 1976; 25:1489-94. [PMID: 182169 DOI: 10.1016/0006-2952(76)90066-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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48
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Infulence of hormones and medium composition on the degradation of phosphoenolpyruvate carboxykinase (GTP) and total protein in Reuber H35 cells. J Biol Chem 1976. [DOI: 10.1016/s0021-9258(17)33384-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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49
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Grimm J. The influence of insulin on various enzyme activities in human and rat hepatoma cells. EUROPEAN JOURNAL OF BIOCHEMISTRY 1976; 64:249-53. [PMID: 179808 DOI: 10.1111/j.1432-1033.1976.tb10294.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
1. Incubation of human and rat hepatoma cells with insulin (1 mU/10(6) cells) decreases their content of adenosine 3':5'-monophosphate by more than half after 1 h and by about a quarter after 4 h. 2. The activities of the ATP-metabolising enzymes, adenylate kinase and Mg2+-adenosine triphosphatase are significantly increased by insulin within 1 h and after 4 h. Activity of succinate dehydrogenase and lactic dehydrogenase showed no change at either time interval. 3. Insulin markedly stimulated glucose 6-phosphate dehydrogenase activity within 1 h but by 4 h the increase was less apparent. Glutamate dehydrogenase activity by contrast was not increased by 1 h but was elevated at 4 h.
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50
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Savage CR, Green PD. Biosynthesis of transcobalamin II by adult rat liver parenchymal cells in culture. Arch Biochem Biophys 1976; 173:691-702. [PMID: 5961 DOI: 10.1016/0003-9861(76)90307-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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