Abstract：
:In the present study we show that monospecific antibody against cytochrome P-450a completely inhibits testosterone 7 alpha-hydroxylation in hepatic microsomes of untreated male or female rats or rats of either sex treated with dexamethasone. These data are in contrast with those of K. Nagata et al. (1987, J. Biol. Chem. 262, 2787-2793) who recently reported that an antibody prepared against cytochrome P-450a completely inhibited testosterone 7 alpha-hydroxylase activity in microsomes from untreated or 3-methylcholanthrene-treated rats but only inhibited 50% of the activity in microsomes from dexamethasone-treated rats. They proposed that dexamethasone treatment of rats induced another testosterone 7 alpha-hydroxylase in rat liver. The discrepancy in the two sets of data was due, at least in part, to the use of a chromatography system by Nagata et al. that is incapable of resolving a number of testosterone metabolites. Dexamethasone treatment of rats leads to a marked increase in the production of several testosterone metabolites, including 15 beta-hydroxytestosterone which is cochromatographic with 7 alpha-hydroxytestosterone in their chromatography system. Our results indicate that cytochrome P-450a accounts for all of the testosterone 7 alpha-hydroxylase activity in microsomes from dexamethasone-treated rats, and that testosterone 7 alpha-hydroxylation continues to be a useful marker for monitoring cytochrome P-450a in rat hepatic microsomes.
journal_name
Arch Biochem Biophysjournal_title
Archives of biochemistry and biophysicsauthors
Levin W,Thomas PE,Ryan DE,Wood AWdoi
10.1016/0003-9861(87)90386-9subject
Has Abstractpub_date
1987-11-01 00:00:00pages
630-5issue
2eissn
0003-9861issn
1096-0384pii
0003-9861(87)90386-9journal_volume
258pub_type
杂志文章abstract：:Hyperammonemia is a major pathophysiological factor in encephalopathies associated with acute and chronic liver failure. On mouse brain slice preparations we analyzed the effects of ammonium on the characteristics of corticostriatal long-term potentiation (LTP) induced by high-frequency electrical stimulation (HFS) of...
journal_title：Archives of biochemistry and biophysics
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doi：10.1016/j.abb.2013.02.002
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abstract：:Constitutive androstane receptor (CAR) transactivation is enhanced by p160 coactivators, which include three members, SRC-1, SRC-2, and SRC-3. Each of the p160 coactivators enhanced mouse CAR (mCAR) transactivation of the CYP2B1 phenobarbital (PB)-responsive enhancer in transfected cultured cells and mouse hepatocytes...
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doi：10.1016/j.abb.2007.09.005
更新日期：2007-12-01 00:00:00
abstract：:The thermal denaturation of clathrin-coated vesicles isolated from bovine brain tissue has been studied by differential scanning calorimetry and has been compared to basket structures reformed from isolated triskelion trimers of clathrin and to isolated triskelions. The coated vesicles and reformed baskets displayed s...
journal_title：Archives of biochemistry and biophysics
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doi：10.1016/0003-9861(89)90502-x
更新日期：1989-09-01 00:00:00
abstract：:We recently cloned a rat brain agmatinase-like protein (ALP) whose amino acid sequence greatly differs from other agmatinases and exhibits a LIM-like domain close to its carboxyl terminus. The protein was immunohistochemically detected in the hypothalamic region and hippocampal astrocytes and neurons. We now show that...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2011.05.003
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journal_title：Archives of biochemistry and biophysics
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doi：10.1016/j.abb.2013.07.001
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journal_title：Archives of biochemistry and biophysics
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doi：10.1006/abbi.1997.9968
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2004.10.020
更新日期：2005-02-01 00:00:00
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(92)90060-a
更新日期：1992-01-01 00:00:00
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(86)90230-4
更新日期：1986-03-01 00:00:00
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1999.1426
更新日期：1999-11-15 00:00:00
abstract：:The objective of this study was to determine if oxidative stress/damage is a possible causal factor in the senescence-related loss of brain functions in the mouse. If such a relationship indeed existed, it was expected that oxidative protein damage would increase with age within regions of the brain associated with se...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1996.0380
更新日期：1996-09-01 00:00:00
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(83)90371-5
更新日期：1983-11-01 00:00:00
abstract：:MicroRNA-342-3p (miR-342) has been shown to act as a tumor-suppressor in different cancer types. However, the role and therapeutic implications of miR-342 via modulation of Cofilin 1 (CFL1) has not been studied in any type of cancer. Given the importance of Cofilin signalling in breast, this study was undertaken to ex...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2020.108385
更新日期：2020-07-15 00:00:00
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(88)90121-x
更新日期：1988-02-15 00:00:00
abstract：:The cardiac contraction-relaxation cycle is controlled by a sophisticated set of machinery. Of particular interest, is the revelation that allosteric networks transmit effects of binding at one site to influence troponin complex dynamics and structural-mediated signaling in often distal, functional sites in the myofil...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
doi：10.1016/j.abb.2018.12.026
更新日期：2019-03-15 00:00:00
abstract：:Putidaredoxin reductase (PdR), an FAD-containing protein, mediates the transfer of electrons from NADH to putidaredoxin in the cytochrome P-450cam-dependent oxidation of camphor. Using stopped-flow spectrophotometry, reduction of putidaredoxin reductase by NADH (70 microM) at 4 degrees C appeared to be a pseudo-first-...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(88)90233-0
更新日期：1988-10-01 00:00:00
abstract：:We previously reported that rat testis and porcine testis contain a physicochemically indistinguishable Mr 32,000 calmodulin-binding protein, which we named "calspermin." In this study, antiserum against calspermin from porcine testis was raised in a rabbit, and a radioimmunoassay was developed. The antiserum reacted ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(87)90299-2
更新日期：1987-05-15 00:00:00
abstract：:Functional concerns regarding hemoglobin-based red cell substitutes have generally centered on two parameters: (a) oxygen binding and delivery properties and (b) stabilization of the hemoglobin tetramer to prevent dimerization. Strategic chemical cross-linking and site-directed mutagenesis have produced proteins that ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1995.1061
更新日期：1995-01-10 00:00:00
abstract：:In an effort to identify and characterize minor forms of human liver cytochrome P450, immunoblot analyses of microsome samples were developed with antibodies to various P450s that recognized multiple human P450s. Four P450s were recognized in immunoblot analyses of human liver microsome samples developed with an antib...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1993.1506
更新日期：1993-10-01 00:00:00
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2001.2613
更新日期：2001-12-15 00:00:00
abstract：:Increasing evidence suggests that long non-coding RNAs (lncRNAs) are implicated with chemoresistance of cancers. However, their functional role and molecular mechanisms in colorectal cancer (CRC) chemoresistance are still largely unclear. In this work, we aimed to investigate the functional role of lncRNA cancer susce...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2019.01.005
更新日期：2019-03-15 00:00:00
abstract：:Biophysical evidences suggest that transthyretin (TTR) tetramer dissociation to the monomeric intermediate and subsequent polymerization leads to amyloid fibril formation, which is implicated in the pathogenesis of familial amyloid polyneuropathy (FAP) and senile systemic amyloidosis (SSA). Hence, inhibition of fibril...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2009.02.013
更新日期：2009-05-15 00:00:00
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journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/s0003-9861(03)00275-3
更新日期：2003-07-15 00:00:00
abstract：:The effects of orally administered secondary autoxidation products of linoleic acid in rat liver were investigated. Their administration led to two toxic effects on hepatic carbohydrate metabolism, as compared to the administration of saline or linoleic acid used as controls. One effect was depletion of glucose 6-phos...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(87)90476-0
更新日期：1987-11-15 00:00:00
abstract：:A procedure was developed for the purification of an acetone-inducible form of cytochrome P-450 (P-450ac) to electrophoretical homogeneity from liver microsomes of acetone-treated rats. The P-450ac preparation containing 16.0 to 16.5 nmol P-450/mg protein moved as a single protein band with an estimated molecular weig...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(86)90373-5
更新日期：1986-12-01 00:00:00
abstract：:The remarkable success of therapeutic applications of immunoglobulin G (IgG) in form of monoclonal antibodies and pooled immunoglobulin G preparations has directed attention to this class of glycoproteins. It is commonly appreciated that oligosaccharides attached to the Fc-region play a critical role in the biological...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
doi：10.1016/j.abb.2012.05.011
更新日期：2012-10-15 00:00:00
abstract：:The effects of nitrous oxide inactivation of the vitamin B12-dependent enzyme, methionine synthetase, on the distribution of folic acid derivatives in rat bone marrow cells, kidney, brain, and liver were determined. Methionine synthetase activity was decreased by about 90% in bone marrow cells, kidney, and brain and b...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(86)90114-1
更新日期：1986-01-01 00:00:00
abstract：:The chemical versatility of the flavin coenzyme is nearly unparalleled in enzyme catalysis. An interesting illustration of this versatility can be found in the reaction catalyzed by the type II isopentenyl diphosphate:dimethylallyl diphosphate isomerase (IDI-2) - an enzyme that interconverts the two essential isoprene...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
doi：10.1016/j.abb.2017.05.017
更新日期：2017-10-15 00:00:00
abstract：:It is widely accepted that the function of human renalase is to oxidize catecholamines in blood. However, this belief is based on experiments that did not account for slow, facile catecholamine autoxidation reactions. Recent evidence has shown that renalase has substrates with which it reacts rapidly. The reaction cat...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2015.05.016
更新日期：2015-08-01 00:00:00
abstract：:Site-mutations were introduced into putative cation binding site 1 of the H,K-ATPase at glu-797, thr-825, and glu-938. The side chain oxygen of each was not essential but the mutations produced different activation and inhibition kinetics. Site mutations thr-825 (ala, leu) and glu-938 (ala, gln) modestly decreased the...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2000.2243
更新日期：2001-03-01 00:00:00
