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[PMID]:22822379
[Au] Autor:Teta R; Della Sala G; Renga B; Mangoni A; Fiorucci S; Costantino V
[Ad] Endereço:The NeaNat Group, Department of Chemistry of Natural Products, University of Naples Federico II, Via D Montesano 49, 80131 Napoli, Italy. roberta.teta@unina.it
[Ti] Título:Chalinulasterol, a chlorinated steroid disulfate from the Caribbean sponge Chalinula molitba. Evaluation of its role as PXR receptor modulator.
[So] Source:Mar Drugs;10(6):1383-90, 2012 Jun.
[Is] ISSN:1660-3397
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Chalinulasterol (1) a new chlorinated sterol disulfate was isolated from the Caribbean sponge Chalinula molitba. Its structure was elucidated using mass spectrometry and NMR experiments. The possible role of chalinulasterol as modulator of the PXR nuclear receptor was investigated but, in spite of the close structural relationship with the PXR agonist solomonsterol A (2), it showed no activity. The structural requirements for the PXR nuclear receptor activity were discussed.
[Mh] Termos MeSH primário: Poríferos/química
Receptores Citoplasmáticos e Nucleares/metabolismo
Receptores de Esteroides/metabolismo
Esteroides Clorados/química
Esteroides Clorados/farmacologia
[Mh] Termos MeSH secundário: Animais
Região do Caribe
Linhagem Celular Tumoral
Células Hep G2
Seres Humanos
Espectroscopia de Ressonância Magnética/métodos
Espectrometria de Massas/métodos
Esteroides Clorados/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Receptors, Cytoplasmic and Nuclear); 0 (Receptors, Steroid); 0 (Steroids, Chlorinated); 0 (pregnane X receptor)
[Em] Mês de entrada:1212
[Cu] Atualização por classe:150224
[Lr] Data última revisão:
150224
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120724
[St] Status:MEDLINE
[do] DOI:10.3390/md10061383


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[PMID]:22001566
[Au] Autor:Yoshimoto FK; Desilets MC; Auchus RJ
[Ad] Endereço:Division of Endocrinology & Metabolism, Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX 75390-8857, United States.
[Ti] Título:Synthesis of halogenated pregnanes, mechanistic probes of steroid hydroxylases CYP17A1 and CYP21A2.
[So] Source:J Steroid Biochem Mol Biol;128(1-2):38-50, 2012 Jan.
[Is] ISSN:1879-1220
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The human steroidogenic cytochromes P450 CYP17A1 (P450c17, 17α-hydroxylase/17,20-lyase) and CYP21A2 (P450c21, 21-hydroxylase) are required for the biosynthesis of androgens, glucocorticoids, and mineralocorticoids. Both enzymes hydroxylate progesterone at adjacent, distal carbon atoms and show limited tolerance for substrate modification. Halogenated substrate analogs have been employed for many years to probe cytochrome P450 catalysis and to block sites of reactivity, particularly for potential drugs. Consequently, we developed efficient synthetic approaches to introducing one or more halogen atom to the 17- and 21-positions of progesterone and pregnenolone. In particular, novel 21,21,21-tribromoprogesterone and 21,21,21-trichloroprogesterone were synthesized using the nucleophilic addition of either bromoform or chloroform anion onto an aldehyde precursor as the key step to introduce the trihalomethyl moieties. When incubated with microsomes from yeast expressing human CYP21A2 or CYP17A1 with P450-oxidoreductase, CYP21A2 metabolized 17-fluoroprogesterone to a single product, whereas incubations with CYP17A1 gave no products. Halogenated steroids provide a robust system for exploring the substrate tolerance and catalytic plasticity of human steroid hydroxylases.
[Mh] Termos MeSH primário: Microssomos/enzimologia
Pregnanos/síntese química
Esteroide 17-alfa-Hidroxilase/química
Esteroide 21-Hidroxilase/química
Esteroides Bromados/síntese química
Esteroides Clorados/síntese química
Esteroides Fluorados/síntese química
[Mh] Termos MeSH secundário: Colesterol Oxidase/química
Cromatografia Líquida de Alta Pressão
Ensaios Enzimáticos
Seres Humanos
Microssomos/química
Oxirredução
Pregnanos/química
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
Esteroide 17-alfa-Hidroxilase/metabolismo
Esteroide 21-Hidroxilase/metabolismo
Esteroides Bromados/química
Esteroides Clorados/química
Esteroides Fluorados/química
Especificidade por Substrato
Leveduras
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Pregnanes); 0 (Recombinant Proteins); 0 (Steroids, Brominated); 0 (Steroids, Chlorinated); 0 (Steroids, Fluorinated); EC 1.1.3.6 (Cholesterol Oxidase); EC 1.14.14.16 (CYP21A2 protein, human); EC 1.14.14.16 (Steroid 21-Hydroxylase); EC 1.14.14.19 (CYP17A1 protein, human); EC 1.14.14.19 (Steroid 17-alpha-Hydroxylase)
[Em] Mês de entrada:1202
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:111018
[St] Status:MEDLINE
[do] DOI:10.1016/j.jsbmb.2011.09.007


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[PMID]:19874345
[Au] Autor:Kasperkiewicz M; Hoppe U; Zillikens D; Schmidt E
[Ad] Endereço:Department of Dermatology, University of Lübeck, 23538 Lübeck, Germany.
[Ti] Título:Relapse-associated autoantibodies to BP180 in a patient with anti-p200 pemphigoid.
[So] Source:Clin Exp Dermatol;35(6):614-7, 2010 Aug.
[Is] ISSN:1365-2230
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Anti-p200 pemphigoid and bullous pemphigoid (BP) are autoimmune subepidermal blistering diseases characterized by autoantibodies to a 200-kDa dermal antigen (p200) and two hemidesmosomal proteins (BP180 and BP230), respectively. We report a 70-year-old man with haemorrhagic blisters, widespread crusted erosions, and the immunopathological characteristics of anti-p200 pemphigoid. Treatment with doxycycline, topical corticosteroids and immunoadsorption led to rapid clinical remission. However, 19 weeks later, a relapse occurred with generalized itchy urticarial erythema and tense blisters. At this time, both strong dermal and epidermal IgG staining was detected by indirect immunofluorescence microscopy on salt-split skin, and autoantibodies against both p200 and the 16th noncollagenous (NC16A) domain of BP180 were found. Interestingly, the relapse was associated not only with the detection of autoantibodies to a second autoantigen (BP180), but also with an altered clinical phenotype. This case was a unique occasion to directly monitor the emergence of intermolecular epitope spreading during the course of an autoimmune bullous disorder.
[Mh] Termos MeSH primário: Antibacterianos/uso terapêutico
Autoanticorpos/imunologia
Autoantígenos/imunologia
Colágenos não Fibrilares/imunologia
Penfigoide Bolhoso/imunologia
Esteroides Clorados/uso terapêutico
[Mh] Termos MeSH secundário: Idoso
Clobetasol/uso terapêutico
Doxiciclina/uso terapêutico
Seres Humanos
Masculino
Penfigoide Bolhoso/tratamento farmacológico
Penfigoide Bolhoso/patologia
Recidiva
Fatores de Tempo
Resultado do Tratamento
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Autoantibodies); 0 (Autoantigens); 0 (Non-Fibrillar Collagens); 0 (Steroids, Chlorinated); 0 (collagen type XVII); ADN79D536H (Clobetasol); N12000U13O (Doxycycline)
[Em] Mês de entrada:1102
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:091031
[St] Status:MEDLINE
[do] DOI:10.1111/j.1365-2230.2009.03731.x


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[PMID]:16039525
[Au] Autor:Marquis JC; Hillier SM; Dinaut AN; Rodrigues D; Mitra K; Essigmann JM; Croy RG
[Ad] Endereço:Department of Chemistry and Biological Engineering Division, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
[Ti] Título:Disruption of gene expression and induction of apoptosis in prostate cancer cells by a DNA-damaging agent tethered to an androgen receptor ligand.
[So] Source:Chem Biol;12(7):779-87, 2005 Jul.
[Is] ISSN:1074-5521
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The goal of our work was the design of DNA-damaging agents that disrupt both DNA repair and signaling pathways in prostate tumor cells. A DNA alkylator (N,N-bis-2-chloroethyl aniline) was linked to a steroid ligand (17beta-hyroxy-estra-Delta(4(5),9(10))-3-one) to produce a complex molecule (11beta-dichloro) that forms DNA adducts that bind the androgen receptor (AR). We speculated that DNA adducts in an AR-DNA adduct complex would be camouflaged from DNA repair proteins that would otherwise remove the adducts in prostate cancer cells. Furthermore, transcription dependent on the AR would be antagonized by AR redistribution to sites distant from AR-driven promoters. The anticancer potential of 11beta-dichloro was demonstrated against prostate cancer cells in vitro and in vivo. 11beta-dichloro induces a unique pattern of gene disruption, induces apoptosis in apoptosis-resistant cells, and shows promising anticancer activity in animals.
[Mh] Termos MeSH primário: Apoptose/efeitos dos fármacos
Dano ao DNA/efeitos dos fármacos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos
Substâncias Intercalantes/farmacologia
Neoplasias da Próstata/patologia
Receptores Androgênicos/metabolismo
[Mh] Termos MeSH secundário: Antagonistas de Receptores de Andrógenos
Androgênios
Animais
Adutos de DNA/química
Adutos de DNA/metabolismo
Estradiol/farmacologia
Ligantes
Masculino
Neoplasias da Próstata/genética
Esteroides Clorados/farmacologia
Células Tumorais Cultivadas
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.; RESEARCH SUPPORT, U.S. GOV'T, P.H.S.
[Nm] Nome de substância:
0 (Androgen Receptor Antagonists); 0 (Androgens); 0 (DNA Adducts); 0 (Intercalating Agents); 0 (Ligands); 0 (Receptors, Androgen); 0 (Steroids, Chlorinated); 4TI98Z838E (Estradiol)
[Em] Mês de entrada:0510
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:050726
[St] Status:MEDLINE


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[PMID]:15923016
[Au] Autor:Minato K; Honma S; Shinohara Y; Hashimoto T
[Ad] Endereço:Safety & Pharmacokinetics Research Department, Teikoku Hormone Mfg. Co. Ltd., 1604 Shimosakunobe, Takatsu-ku, Kawasaki-shi, Kanagawa 213-8522, Japan. minato-k@teioku-hormone.co.jp
[Ti] Título:Metabolism of osaterone acetate in dogs and humans.
[So] Source:Steroids;70(9):563-72, 2005 Aug.
[Is] ISSN:0039-128X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Osaterone acetate (17 alpha-acetoxy-6-chloro-2-oxa-4,6-pregnadiene-3,20-dione; OA) is a steroidal antiandrogen. In order to clarify the species differences, metabolites of OA were examined in plasma, urine, and feces of dogs and humans after oral administration of OA. Eleven metabolites in plasma, urine, and feces were identified by their spectral properties and comparison to appropriate standards. The primary routes of OA metabolism involve 11 beta-, 15 beta- and 21-hydroxylation, 17 alpha-deacetylation, and dechlorination. Other metabolites arise from combinations of these pathways to form multiple oxidized metabolites. All metabolites observed in humans occurred in dogs. 11 beta-Hydroxylated metabolites (11 beta-OH OA and 11-oxo OA) were found in the plasma and urine of dogs, but there was no evidence of their presence in humans. 11 beta-Hydroxylation of exogenous steroids represents a distinctive biotransformation pathway.
[Mh] Termos MeSH primário: Acetato de Clormadinona/análogos & derivados
[Mh] Termos MeSH secundário: Acetilação
Administração Oral
Antagonistas de Androgênios/sangue
Antagonistas de Androgênios/farmacocinética
Antagonistas de Androgênios/urina
Animais
Acetato de Clormadinona/química
Acetato de Clormadinona/metabolismo
Acetato de Clormadinona/farmacocinética
Cães
Fezes/química
Seres Humanos
Hidroxilação
Estrutura Molecular
Especificidade da Espécie
Esteroides Clorados/metabolismo
Esteroides Clorados/farmacocinética
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Androgen Antagonists); 0 (Steroids, Chlorinated); 0SY050L61N (Chlormadinone Acetate); FR26FSV5EZ (osaterone acetate)
[Em] Mês de entrada:0512
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:050601
[St] Status:MEDLINE


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[PMID]:15041288
[Au] Autor:Moriyama K; Matsufuji H; Chino M; Takeda M
[Ad] Endereço:Department of Food Science and Technology, College of Bioresource Sciences, Nihon University, 1866 Kameino, Fujisawa, Kanagawa 252-8510, Japan.
[Ti] Título:Identification and behavior of reaction products formed by chlorination of ethynylestradiol.
[So] Source:Chemosphere;55(6):839-47, 2004 May.
[Is] ISSN:0045-6535
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Six products were formed by reaction of ethynylestradiol (EE2) with sodium hypochlorite in buffered solutions. 4-Chloroethynylestradiol (4-ClEE2) and 2,4-dichloroethynylestradiol (2,4-diClEE2) were identified as the two major reaction products, using preparative HPLC, MS, and NMR. When EE2 reacted with chlorine at different pHs (pH 5, 7, and 9) or chlorine concentrations (0.2, 1, 2, and 5 mmol/l, corresponding to molar ratios to EE2, 1, 5, 10, and 25, respectively), the formation of 4-ClEE2 and 2,4-diClEE2 was observed under the above conditions, and the highest yields were 20 and 52 mol%, respectively. EE2 was consumed almost completely within 5 min of chlorination by addition of chlorine of more than 1 mmol/l (molar ratio to EE2, 5). On the other hand, the two products existed in highly chlorinated solutions after 60 min (4ClEE2, 1-6 mol%; 2,4-diClEE2, 3-25 mol%). The estrogenic activities of 4-ClEE2 by estrogen receptor alpha or beta binding assay were similar to those of the parent EE2, and the activities of 2,4-diClEE2 were lower about 10 times.
[Mh] Termos MeSH primário: Etinilestradiol/química
Hipoclorito de Sódio/química
Esteroides Clorados/química
[Mh] Termos MeSH secundário: Cromatografia Líquida de Alta Pressão
Ensaio de Imunoadsorção Enzimática
Concentração de Íons de Hidrogênio
Cinética
Espectrometria de Massas
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Steroids, Chlorinated); 423D2T571U (Ethinyl Estradiol); DY38VHM5OD (Sodium Hypochlorite)
[Em] Mês de entrada:0406
[Cu] Atualização por classe:131121
[Lr] Data última revisão:
131121
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:040326
[St] Status:MEDLINE


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[PMID]:8048148
[Au] Autor:Schwede W; Cleve A; Neef G; Ottow E; Stöckemann K; Wiechert R
[Ad] Endereço:Research Laboratories of Schering AG, Berlin, Germany.
[Ti] Título:Synthesis and biological activity of 17-chloro-16(17) unsaturated D-homo antiprogestins.
[So] Source:Steroids;59(3):176-80, 1994 Mar.
[Is] ISSN:0039-128X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:An efficient approach to 17-chloro-16(17) unsaturated D-homo antiprogestins is described. The key steps of the synthesis are a ring-expansion via dichlorocarbene addition to a 17-silyl enol ether and a palladium catalyzed coupling of an 11 beta-(4-aryltriflate) with tributyl(1-ethoxyethenyl)stannane or diethyl(3-pyridinyl)-borane. The new progesterone antagonists were tested for their biological activities and compared to those of known antiprogestins.
[Mh] Termos MeSH primário: Progestinas/antagonistas & inibidores
Esteroides Clorados/síntese química
Esteroides Clorados/farmacologia
[Mh] Termos MeSH secundário: Aborto Induzido/métodos
Animais
Feminino
Estrutura Molecular
Gravidez
Ratos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Progestins); 0 (Steroids, Chlorinated)
[Em] Mês de entrada:9408
[Cu] Atualização por classe:031114
[Lr] Data última revisão:
031114
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:940301
[St] Status:MEDLINE


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[PMID]:2229972
[Au] Autor:Newport ML; Lane LB; Stuchin SA
[Ad] Endereço:Hospital for Joint Diseases, Orthopaedic Institute, New York, NY.
[Ti] Título:Treatment of trigger finger by steroid injection.
[So] Source:J Hand Surg Am;15(5):748-50, 1990 Sep.
[Is] ISSN:0363-5023
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A retrospective study of 235 patients with 338 primary trigger fingers determined the efficacy and safety of steroid injection. Initial treatment consisted of one to three injections of corticosteroid mixed with local anesthetic. Those fingers that failed injection therapy had conventional release of the first annular pulley. Seventy-seven percent of all fingers showed resolution or improvement; 49% after a single injection, 23% after two injections, and 5% after three injections.
[Mh] Termos MeSH primário: Esteroides Clorados/uso terapêutico
Tenossinovite/terapia
[Mh] Termos MeSH secundário: Adolescente
Adulto
Idoso
Idoso de 80 Anos ou mais
Feminino
Seres Humanos
Injeções Intradérmicas
Masculino
Meia-Idade
Prognóstico
Estudos Retrospectivos
Esteroides Clorados/administração & dosagem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Steroids, Chlorinated)
[Em] Mês de entrada:9012
[Cu] Atualização por classe:090608
[Lr] Data última revisão:
090608
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:900901
[St] Status:MEDLINE


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[PMID]:2731822
[Au] Autor:Weber N
[Ad] Endereço:Bundesanstalt für Fettforschung, H.P. Kaufmann-Institut, Münster, Federal Republic of Germany.
[Ti] Título:Studies on intestinal absorption, distribution and metabolism of 3 beta-chloro[4-14C]cholest-5-ene and 3 beta-chloro[4-14C]stigmast-5-ene in mice.
[So] Source:Food Chem Toxicol;27(4):259-63, 1989 Apr.
[Is] ISSN:0278-6915
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A method for the analysis of 3 beta-chloro steroids by high-performance liquid chromatography is described. These compounds are known to occur in commercial protein hydrolysates. The gastro-intestinal absorption, distribution and metabolism of chlorinated steroids were studied after their intragastric application to mice. At 2 hr after stomach intubation of 3 beta-chloro[4-14C]cholest-5-ene and 3 beta-chloro-[4-14C]stigmast-5-ene, large proportions of radioactivity had passed through the small intestine and were found to be concentrated in the contents of the caecum and colon. Very small amounts of 3 beta-chlorocholest-5-ene were absorbed by the intestinal mucosa and distributed to organs and tissues outside the alimentary canal, whereas intestinal permeability of 3 beta-chlorostigmast-5-ene was negligible. After administration of labelled 3 beta-chlorocholest-5-ene, the highest value of radioactivity, 120 Bq/g tissue, outside the intestinal tract was detected in liver. Altogether, less than 0.5% of the total radioactivity applied to the animals was found to be transported through the intestinal wall and less than 0.5% of the total radioactivity was detected in various metabolites. In general, 3 beta-chlorostigmast-5-ene was transported in smaller proportions and metabolized to a lesser extent than the corresponding cholesterol derivative. Moreover, metabolites of the two radioactive substrates formed by enzymatic attack of enteric micro-organisms were not detected in the contents of the caecum and colon. It appears that 3 beta-chlorinated steroids are fairly stable products that are metabolized poorly both by the cells of the intestinal mucosa and by enteric micro-organisms of mice.
[Mh] Termos MeSH primário: Colestenos/farmacocinética
Sitosteroides
Esteroides Clorados/farmacocinética
[Mh] Termos MeSH secundário: Animais
Colestenos/administração & dosagem
Colestenos/análise
Cromatografia Líquida de Alta Pressão/métodos
Fezes/análise
Feminino
Absorção Intestinal
Intubação Gastrointestinal
Lipídeos/análise
Camundongos
Feijão de Soja/análise
Distribuição Tecidual
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cholestenes); 0 (Lipids); 0 (Sitosterols); 0 (Steroids, Chlorinated); 33999-15-4 (3-chlorostigmast-5-ene); 39EHZ05V39 (3-chlorocholest-5-ene)
[Em] Mês de entrada:8907
[Cu] Atualização por classe:121115
[Lr] Data última revisão:
121115
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:890401
[St] Status:MEDLINE


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[PMID]:2566465
[Au] Autor:Halpert J; Jaw JY; Cornfield LJ; Balfour C; Mash EA
[Ad] Endereço:Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson 85721.
[Ti] Título:Selective inactivation of rat liver cytochromes P-450 by 21-chlorinated steroids.
[So] Source:Drug Metab Dispos;17(1):26-31, 1989 Jan-Feb.
[Is] ISSN:0090-9556
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The inactivation by 21-chlorinated steroids of rat liver cytochromes P-450 involved in the hydroxylation of progesterone and androstenedione has been investigated. Preincubation of intact liver microsomes from phenobarbital-treated rats with 21-chloropregnenolone, 21,21-dichloropregnenolone, or 21,21-dichloroprogesterone in the presence of NADPH caused a time-dependent decrease in progesterone 21-hydroxylase and in progesterone or androstenedione 6 beta-hydroxylase activity but had negligible or only minor effects on five other steroid hydroxylases. The compounds differed, however, with regard to the relative rate constants for inactivation of the 21- and 6 beta-hydroxylases. For example, 21,21-dichloroprogesterone and 21,21-dichloropregnenolone inactivated the progesterone 6 beta-hydroxylase at similar rates, but the dichloroprogesterone was a more effective inactivator of the 21-hydroxylase. The results indicate that the introduction of a dichloromethyl group into a substrate bearing a methyl group normally hydroxylated by only one or a few isozymes of cytochrome P-450 may be a rational means of designing isozyme-selective inhibitors but that target and nontarget enzymes may not totally retain the regioselectivity they exhibit towards the underivatized substrate.
[Mh] Termos MeSH primário: Sistema Enzimático do Citocromo P-450/metabolismo
Esteroides Clorados/farmacologia
[Mh] Termos MeSH secundário: Animais
Ativação Enzimática/efeitos dos fármacos
Masculino
Ratos
Ratos Endogâmicos
Esteroide Hidroxilases/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, P.H.S.
[Nm] Nome de substância:
0 (Steroids, Chlorinated); 9035-51-2 (Cytochrome P-450 Enzyme System); EC 1.14.- (Steroid Hydroxylases)
[Em] Mês de entrada:8907
[Cu] Atualização por classe:071114
[Lr] Data última revisão:
071114
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:890101
[St] Status:MEDLINE



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BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde