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2.
Forensic Sci Int ; 326: 110918, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34325112

RESUMEN

The past decade has seen an increase in the development and availability of a broad category of drugs, known as new psychoactive substances (NPS). NPS are challenging for public health authorities, therefore the two major drug monitoring bodies - the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) and the United Nations Office on Drugs and Crime (UNODC) - have implemented the EU Early Warning System (EWS) and Early Warning Advisory (EWA), respectively. While these monitoring systems are informative, it is difficult to keep up with the constant and rapid developmental rate of NPS. The EMCDDA has recognised the need for an alternative and technologically derived early warning system. The aim of this research is to determine whether Google Trends and drug discussion forum data can be used to complement early warning systems for NPS. Forty-eight substances were used in this study and classed into groups based on their chemical structure, following the UNODC classification system. Google Trends data (time range: 2004-2019) and drug forum data (time range: 2003-2018) were extracted for each substance and visual trend profiles were created for class groups as well as individual substances. Analysis was conducted to determine when a substance first appeared on Google Trends and a drug discussion forum as well as their trends over time. This date of first appearance was then compared to the date the substance was first reported to UNODC. Of the three data sources utilised, substances were most likely to appear on Google Trends first. Amongst the different classes of NPS, discernible trends ('block', 'successive', and 'generational' trends) were observed. These trends reflect the evolution of the manufacture of substances or generations of substances that has been observed in the literature. For example, in the synthetic cannabinoids' category, a generational trend is observed that corresponds to the different generations of synthetic cannabinoids. When comparing Google Trends and Drugs-Forum directly, the order of appearance and duration of presence for substances aligns accurately for most classes. Google Trends showed the emergence, persistence, or transient nature of substances, which could direct the focus of law enforcement, health organisation and laboratory resources towards a limited number of substances. When one considers the reliance of individual information seeking on the Web as well as the prominence of NPS on the Web, it becomes clear that Google Trends and drug discussion forums could be used as a complement to current early warning systems.

5.
Handb Exp Pharmacol ; 252: 51-67, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29896655

RESUMEN

The phenomenon of new psychoactive substances (NPS), which came to the attention of the wider international community at the beginning of the 2010s, has been unprecedented in terms of the sheer number of substances, their rate of emergence, chemical diversity, and range of pharmacological effects. In particular, the chemical diversity has been a challenge to promoting a better understanding of the NPS market - a fundamental requirement for effective policy decisions and interventions. This manuscript highlights the significant chemical diversity of NPS and describes an alternative, complementary, and pragmatic classification based on pharmacological effects, which aligns NPS to traditional controlled drugs and enhances understanding of the phenomenon. It further reviews actions taken at the international level to address the NPS issue, including changes in the scope of control of some NPS and the enhancement of the United Nations Early Warning Advisory on NPS to deal with the dynamics and evolution of the market.


Asunto(s)
Legislación de Medicamentos , Psicotrópicos/provisión & distribución , Naciones Unidas
6.
Forensic Sci Int ; 274: 2-6, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27899215

RESUMEN

The nature of the global drugs market has evolved rapidly and has become more complex with the emergence of new psychoactive substances (NPS), some of which have been associated with increased abuse, hospital emergency admissions and sometimes fatalities. NPS are characterized by geographic heterogeneity, with some only transient in nature and others not satisfying the criteria for harm required for international control. Consequently, a pragmatic response of the international community is to prioritize the most harmful, persistent and prevalent substances for action - an objective, which is hampered by the paucity of data on harms. The report describes a United Nations Office on Drugs and Crime (UNODC) initiative, in collaboration with the International Association of Forensic Toxicologists (TIAFT), to collect, analyze and share toxicology data at a global level to reinforce the ability of the international community in making informed decisions using a scientific evidence-based approach, in identifying the most harmful NPS.


Asunto(s)
Control de Medicamentos y Narcóticos , Toxicología Forense , Cooperación Internacional , Psicotrópicos/efectos adversos , Adolescente , Adulto , Recolección de Datos , Drogas de Diseño/efectos adversos , Drogas de Diseño/envenenamiento , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Psicotrópicos/envenenamiento , Trastornos Relacionados con Sustancias/epidemiología , Adulto Joven
7.
Philos Trans R Soc Lond B Biol Sci ; 370(1674)2015 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-26101290

RESUMEN

The analysis of substances of abuse remains one of the most matured areas in forensic science with a strong scientific basis, namely analytical chemistry. The current evolving drug markets, characterized by the global emergence of new psychoactive substances (NPS) and the need for forensic scientists to identify an unprecedented and ever-increasing number of NPS, presents a unique challenge to this discipline. This article looks at the current situation with NPS at the global level, and the challenges posed to the otherwise technically robust forensic science discipline of analysis of substances of abuse. It discusses the preparedness of forensic science to deal with the current situation and identifies the need for a shift in forensic science practice, especially one which embraces research and looks beyond normal casework in order to provide the much needed data for developing effective policy responses to the NPS problem.


Asunto(s)
Toxicología Forense/métodos , Psicotrópicos/química , Control de Medicamentos y Narcóticos/legislación & jurisprudencia , Control de Medicamentos y Narcóticos/tendencias , Legislación de Medicamentos , National Academy of Sciences, U.S. , Estados Unidos
8.
Gene ; 515(1): 155-8, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23201897

RESUMEN

BACKGROUND/AIMS: The aim of the present study is to probe the potential association between previously-reported GARP2 mutations and retinitis pigmentosa (RP) using Scottish RP patients and controls. METHODS: Exons 4, 5 and 8 in DNA from blood or buccal samples (130 autosomal recessive and simplex RP patients, 31 controls) were amplified and analysed for single-strand conformational polymorphism by capillary electrophoresis (CE-SSCP) and confirmed by sequencing. RESULTS: The p.Arg86Gln mutation in exon 4 was found in just one patient (out of 130), and in 10 of the 31 unaffected subjects. All of these occurrences were in people of West African origin (patient and controls). Two polymorphisms in exon 5, p.His100Arg and p.Gly109Gly, and a c.534+20A>G change in the intronic region flanking the 3' end of exon 8 were also found not to be associated with RP. CONCLUSIONS: The Scottish population examined here had no mutations in the GARP2 exons surveyed that could be associated with RP. The p.Arg86Gln mutation actually appears to be a polymorphism common in ethnic West Africans and not associated with RP. This change may provide a useful marker for West African ancestry.


Asunto(s)
Sustitución de Aminoácidos , Población Negra/genética , Polimorfismo de Nucleótido Simple , África Occidental , Secuencia de Aminoácidos , Secuencia de Bases , Estudios de Casos y Controles , Canales Catiónicos Regulados por Nucleótidos Cíclicos , Exones , Humanos , Datos de Secuencia Molecular , Retinitis Pigmentosa/genética , Escocia , Alineación de Secuencia , Población Blanca/genética
9.
Anal Bioanal Chem ; 404(1): 239-55, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22618328

RESUMEN

This paper describes the reversed-phase liquid chromatographic behaviour of the trypanocidal quaternary ammonium salt isometamidium chloride and its related compounds on a range of liquid chromatographic phases possessing alkyl and phenyl ligands on the same inert silica. In a parallel study with various extended polar selectivity phases which possessed different hydrophobic/silanophilic (hydrogen bonding) activity ratios, the chromatographic retention/selectivities of the quaternary ammonium salts was shown to be due to a co-operative mechanism between hydrophobic and silanophilic interactions. The highly aromatic and planar isometamidium compounds were found to be substantially retained on stationary phases containing aromatic functionality via strong π-π interactions. The chemometric approach of principal component analysis was used to characterise the chromatographic behaviour of the isometamidium compounds on the differing phases and to help identify the dominant retention mechanism(s). Two-dimensional (temperature/gradient) retention modelling was employed to develop and optimise a rapid liquid chromatography method for the separation of the six quaternary ammonium salts within 2.5 min which would be suitable for bioanalysis using liquid chromatography-mass spectrometry. This is the first reported systematic study of the relationship between stationary phase chemistries and retention/selectivity for a group of quaternary ammonium salts.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cromatografía de Fase Inversa/métodos , Fenantridinas/análisis , Compuestos de Amonio Cuaternario/análisis , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía de Fase Inversa/instrumentación
10.
J Arthroplasty ; 25(1): 118-20, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19056207

RESUMEN

Metal-on-metal resurfacing arthroplasty is associated with elevated circulating levels of cobalt and chromium ions. To establish the long-term safety of metal-on-metal resurfacing arthroplasty, it has been recommended that during clinical follow-up of these patients, the levels of these metal ions in blood be monitored. In this article, we provide information on the distribution of chromium VI ions (the predominant form of chromium released by cobalt-chrome alloys in vivo and in vitro) in blood fractions. Chromium VI is predominantly partitioned into red blood cells compared with plasma (analysis of variance, P < .05). The extent of accumulation in red blood cells is influenced by the anticoagulant used to collect the blood, with EDTA giving a lower partitioning into red cells compared with sodium citrate and sodium heparin.


Asunto(s)
Anticoagulantes/farmacología , Aleaciones de Cromo/farmacocinética , Cromo/sangre , Prótesis de Cadera , Citratos/farmacología , Ácido Edético/farmacología , Eritrocitos/química , Heparina/farmacología , Humanos , Técnicas In Vitro , Plasma/química , Citrato de Sodio
11.
J Med Chem ; 52(11): 3457-63, 2009 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-19422230

RESUMEN

Dimethylallylguanidine, also known as galegine, isolated from Galega officinalis, has been shown to have weight reducing properties in vivo. Substitution of the guanidine group with an N-cyano group and replacement of guanidine with amidine, pyrimidine, pyridine, or the imidazole moieties removed the weight reducing properties when evaluated in BALB/c mice. However, retention of the guanidine and replacement of the dimethylallyl group by a series of functionalized benzyl substituents was shown to exhibit, and in some cases significantly improve, the weight reducing properties of these molecules in BALB/c, ob/ob, and diet induced obesity (DIO) mice models. The lead compound identified, across all models, was 1-(4-chlorobenzyl)guanidine hemisulfate, which gave an average daily weight difference (% from time-matched controls; +/- SEM) of -19.7 +/- 1.0, -11.0 +/- 0.7, and -7.3 +/- 0.8 in BALB/c, ob/ob, and DIO models, respectively.


Asunto(s)
Fármacos Antiobesidad/farmacología , Compuestos de Bencilo/farmacología , Guanidinas/farmacología , Pérdida de Peso/efectos de los fármacos , Animales , Compuestos de Bencilo/síntesis química , Grasas de la Dieta/administración & dosificación , Guanidinas/síntesis química , Guanidinas/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Obesos , Microsomas Hepáticos/metabolismo
12.
J Pharm Pharmacol ; 61(3): 399-406, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19222915

RESUMEN

OBJECTIVES: To measure the metabolism and toxicity of 7-chloro-4-(cyclohexylmethyl)-1-methyl-3,4-dihydro-1H-1,4-benzodiazepine-2,5-dione (BNZ-1) and 4-cyclohexylmethyl-1-methyl-3,4-dihydro-1H-1,4-benzodiazepine-2,5-dione (BNZ-2), two new benzodiazepine analogues found to be effective against Leishmania amastigotes in vitro. METHODS: The metabolism of BNZ-1 and -2 was investigated in isolated rat hepatocytes and rat liver microsomes. The toxicity of the compounds was assessed in a murine macrophage cell line by determining cell viability and reduced glutathione (GSH) content. The metabolism and toxicity of flurazepam was assessed for comparison. KEY FINDINGS: BNZ-1 and BNZ-2 underwent similar metabolic transformations by the liver systems, forming N-demethylated and hydroxylated metabolites, with subsequent O-glucuronidation. Flurazepam and both analogue compounds depleted macrophage GSH levels without affecting cell viability at the concentrations used (up to 100 microM), but only flurazepam inhibited glutathione reductase activity, indicating that it is acting by a different mechanism. CONCLUSIONS: The exact mechanism responsible for GSH depletion is unknown at present. Further experiments are needed to fully understand the effects of BNZs on the parasite GSH analogue, trypanothione, which may be a direct or indirect target for these agents. Pharmacokinetic evaluation of these compounds is required to further progress their development as potential new treatments for leishmaniasis.


Asunto(s)
Benzodiazepinas/toxicidad , Glutatión/efectos de los fármacos , Tripanocidas/toxicidad , Animales , Benzodiazepinas/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Flurazepam/metabolismo , Flurazepam/toxicidad , Glutatión/metabolismo , Hepatocitos/metabolismo , Macrófagos/metabolismo , Masculino , Ratones , Microsomas Hepáticos/metabolismo , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad , Tripanocidas/metabolismo
13.
J Biomed Mater Res A ; 88(2): 543-50, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18306314

RESUMEN

There is increasing concern regarding the long-term biological effects of exposure to low concentrations of metal ions, particularly chromium, in patients following implantation of metal-on-metal hip prostheses. To investigate this, we have evaluated the chronic in vitro response to clinically relevant concentrations of chromium VI in osteoblasts and monocytes over a 4-week period in continuous culture. The cell viability, intracellular reduced glutathione content, glutathione reductase activity and expression, and expression of glutamate cysteine ligase were monitored in both cell types. Monocytes were more susceptible to the toxicity of the metal, and at the end of 4 weeks exposure to 0.5 microM Cr VI, the protein content of cultures had declined to 23.4% +/- 1.0% of control cultures. Both cell types demonstrated temporal increases in reduced glutathione levels, glutathione reductase activity, and glutamate cysteine ligase expression. Only osteoblasts showed a transcriptional increase in reductase expression. Data suggest that both cell types mount an adaptive response to chronic exposure to Cr VI, but this is more potent in osteoblasts, and results in the relative resilience of this cell type to the effects of Cr VI on cell viability.


Asunto(s)
Carcinógenos Ambientales/toxicidad , Cromo/toxicidad , Monocitos/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Animales , Células Cultivadas , Glutatión/metabolismo , Glutatión Reductasa/metabolismo , Prótesis de Cadera/efectos adversos , Humanos , Persona de Mediana Edad , Falla de Prótesis , Ratas
14.
Arch Pharm (Weinheim) ; 341(2): 81-9, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18214840

RESUMEN

The synthesis and biological evaluation of ethyl 8-oxo-5,6,7,8-tetrahydro-thiazolo[3,2-a][1,3]diazepin-3-carboxylate (HIE-124, 4), as a member of a new generation of ultra-short acting hypnotics is described. HIE-124 4 exhibited potent in-vivo activity with a very rapid onset of action and a shorter duration of action with no acute tolerance or noticeable side effects than thiopental sodium. The rat in-vivo and in-vitro metabolic profile of 4 is also described. Urine was pooled from a number of animals and analyzed using electrospray liquid chromatography mass spectrometry (ESI LC-MS). HIE-124 4 was incubated with rat-liver microsomal and rat-liver hepatocyte preparations then similarly analyzed. The only metabolic product of both in-vitro and in-vivo experiments is the carboxylic acid derivative 5. HIE-124 4 has the potential use not only as a pre-anesthetic medication and as anesthesia inducer but also has the potential to be used with thiopental sodium to maintain anesthesia for longer duration.


Asunto(s)
Azepinas/síntesis química , Azepinas/farmacología , Ácidos Carboxílicos/síntesis química , Ácidos Carboxílicos/farmacología , Hipnóticos y Sedantes/síntesis química , Hipnóticos y Sedantes/farmacología , Tiazoles/síntesis química , Tiazoles/farmacología , Animales , Azepinas/metabolismo , Ácidos Carboxílicos/metabolismo , Cromatografía Liquida , Relación Dosis-Respuesta a Droga , Femenino , Hepatocitos/metabolismo , Hipnóticos y Sedantes/metabolismo , Técnicas In Vitro , Masculino , Ratones , Microsomas Hepáticos/metabolismo , Ratas , Ratas Sprague-Dawley , Espectrometría de Masa por Ionización de Electrospray , Relación Estructura-Actividad , Tiazoles/metabolismo
15.
Electrophoresis ; 29(4): 944-51, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18213596

RESUMEN

This simultaneous separation of basic, acidic and neutral analytes by pressure-assisted CEC (pCEC) using a hybrid (tetramethoxysilane and methyltrimethoxysilane) silica-based monolith, chemically modified with octadecyldimethylchlorosilane followed by endcapping with hexamethyldisilazane is described. The endcapping resulted in near Gaussian peaks for highly basic analytes such as nortriptyline without a significant loss in the EOF. The migration behaviour of analytes on this phase could be rationalised based on hydrophobicity, electrophoretic mobility and ion-exchange interactions. The high porosity of the monolith allowed manipulation of the linear velocity of mobile phases by the addition of varying amounts of pressure at the inlet to reduce analysis times and overcome the reversed migration of anionic species towards the detection window in cathodic EOF mode. The concomitant programmed application of pressure (2-4 bar) and voltage (27 kV) facilitated the simultaneous separation of four cationic, four neutral and two anionic compounds in 6 min with efficiencies ranging from 41 000 to 94 000, 57 000 to 77 000 and 180 000 to 210 000 theoretical plates/metre, respectively. The % RSD values of migration times and efficiencies in pCEC mode were less than 3.6 and 7.9%, respectively (n = 5).


Asunto(s)
Electrocromatografía Capilar/métodos , Compuestos Orgánicos/análisis , Aniones/análisis , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Compuestos de Organosilicio/química , Presión , Silanos/química
16.
Electrophoresis ; 29(2): 393-400, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18080248

RESUMEN

CE and hydrogen-deuterium (H/D) exchange MS are useful tools in the analysis and characterisation of peptides. This study reports the facile coupling of these tools in the H/D exchange CE-MS analysis of model and pharmaceutically important peptides, using a sheath flow interface. The peptides varied in mass from 556 (leucine enkephalin) to 1620 Da (bombesin), and in charge state from 0.33 (leucine enkephalin) to 3.0 (substance P). The application of a BGE composed of ammonium formate buffer (25 mM, pD 3.5 in D(2)O (>98% D atom)), a sheath liquid composed of formic acid (0.25% v/v in D(2)O) and ACN (30:70 v/v), and dissolving the samples in a mixture of ACN/D(2)O (50:50 v/v) facilitates complete H/D exchange. Because of complete H/D exchange the ESI mass spectra produced are easy to interpret and comparable to those obtained from LC-MS analysis. The CE-H/D-MS approach has the advantage of requiring lower volumes of deuterated solvents. The b- and y-series fragments produced by using in-source decomposition correspond to those predicted. With the peptides studied, the complete exchange H/D exchange observed with both the molecular and fragment ions helps to confirm both amino acid composition and sequence.


Asunto(s)
Medición de Intercambio de Deuterio/métodos , Electroforesis Capilar/métodos , Espectrometría de Masas/métodos , Péptidos/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Encefalina Leucina/aislamiento & purificación , Goserelina/aislamiento & purificación
17.
Bioorg Med Chem Lett ; 18(1): 72-7, 2008 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18023180

RESUMEN

Ethyl 8-oxo-5,6,7,8-tetrahydro-thiazolo[3,2-a][1,3]diazepin-3-carboxylate (HIE-124, 4) is a member of a new generation of ultra-short acting hypnotics. HIE-124 (4) exhibited potent in vivo activity with a rapid onset of action and a short duration of action, with no acute tolerance or noticeable side effects. The metabolic profile of 4 is also performed. HIE-124 (4) has the potential use as a preanesthetic medication, anesthesia inducer, and could be used with thiopental sodium to maintain anesthesia for longer duration.


Asunto(s)
Azepinas/metabolismo , Azepinas/farmacología , Ácidos Carboxílicos/metabolismo , Ácidos Carboxílicos/farmacología , Hipnóticos y Sedantes/metabolismo , Hipnóticos y Sedantes/farmacología , Tiazoles/metabolismo , Tiazoles/farmacología , Animales , Azepinas/farmacocinética , Ácidos Carboxílicos/farmacocinética , Relación Dosis-Respuesta a Droga , Hipnóticos y Sedantes/síntesis química , Hipnóticos y Sedantes/farmacocinética , Ratones , Tiazoles/farmacocinética
18.
Bioorg Med Chem Lett ; 17(3): 624-7, 2007 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-17113290

RESUMEN

The continual increase in drug resistance; the lack of new chemotherapeutic agents; the toxicity of existing agents and the increasing morbidity with HIV co-infection mean the search for new antileishmanial agents has never been more urgent. We have identified the benzodiazepines as a structural class for antileishmanial hit optimisation, and demonstrated that their in vitro activity is comparable with the clinically used drug, sodium stibogluconate, and that the compounds are not toxic to macrophages.


Asunto(s)
Antiprotozoarios/síntesis química , Antiprotozoarios/farmacología , Benzodiazepinas/síntesis química , Benzodiazepinas/farmacología , Leishmania/efectos de los fármacos , Animales , Gluconato de Sodio Antimonio/farmacología , Antiprotozoarios/toxicidad , Benzodiazepinas/toxicidad , Indicadores y Reactivos , Leishmania donovani/efectos de los fármacos , Dosificación Letal Mediana , Macrófagos/efectos de los fármacos , Macrófagos/parasitología
19.
Electrophoresis ; 26(18): 3445-51, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16110461

RESUMEN

In this study, a porous mixed-mode n-alkyl methacrylate-based monolith has been used in the separation of therapeutic peptides. While the sulfonic acid (SCX) moiety derived from 2-acrylamido-2-methyl-1-propanesulfonic acid supports the generation of a stable electroosmotic flow (EOF) at both acidic and basic pH values, the butyl ligands provide the nonpolar sites for chromatographic resolution. The performance of the monolith was evaluated regarding the influence of pH on chromatographic resolution of peptides. The suitability of the butylmethacrylate/SCX monolith for the analysis of therapeutic peptides containing basic centres, for example arginine, at moderately high pH 9.5 and the stability to repeat injections of a mixture of peptides was demonstrated. Separations with efficiencies as high as 5.0 x 10(5) plates/m were obtained and the migration behaviour of the peptides at both low (2.8) and high (9.5) pH values could be rationalised based on their charge, molecular mass/shape and relative hydrophobicities.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Electroforesis Capilar/métodos , Neuropéptidos/aislamiento & purificación , Cromatografía Líquida de Alta Presión/instrumentación , Estabilidad de Medicamentos , Electroforesis Capilar/instrumentación , Metacrilatos , Neuropéptidos/química
20.
Drug Metab Dispos ; 33(2): 271-81, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15523047

RESUMEN

SB-209247 [(E)-3-[6-[[(2,6-dichlorophenyl)-thio]methyl]-3-(2-phenylethoxy)-2-pyridinyl]-2-propenoic acid], an anti-inflammatory leukotriene B4 receptor antagonist, was associated in beagle dogs but not male rats with an inflammatory hepatopathy. It also produced a concentration-dependent (10-1000 microM) but equal leakage of enzymes from dog and rat precision-cut liver slices. The hepatic metabolism of SB-209247 was investigated with reference to the formation of reactive acyl glucuronides. [14C]SB-209247 (100 micromol/kg) administered i.v. to anesthetized male rats was eliminated by biliary excretion of the acyl glucuronides of the drug and its sulfoxide. After 5 h, 1.03 +/- 0.14% (mean +/- S.E.M., n = 4) of the dose was bound irreversibly to liver tissue. The sulfoxide glucuronide underwent pH-dependent rearrangement in bile more rapidly than did the SB-209247 conjugate. [14C]SB-209247 was metabolized by sulfoxidation and glucuronidation in rat and dog hepatocytes, and approximately 1 to 2% of [14C]SB-209247 (100 microM) became irreversibly bound to cellular material. [14C]SB-209247 sulfoxide and glucuronide were the only metabolites produced by dog, rat, and human liver microsomes in the presence of NADPH and UDP-glucuronic acid (UDPGA), respectively. V(max) values for [14C]SB-209247 glucuronidation by dog, rat, and human microsomes were 2.6 +/- 0.1, 1.2 +/- 0.1, and 0.4 +/- 0.0 nmol/min/mg protein, respectively. Hepatic microsomes from all three species catalyzed UDPGA-dependent but not NADPH-dependent irreversible binding of [14C]SB-209247 (100-250 microM) to microsomal protein. Although a reactive acyl glucuronide was formed by microsomes from every species, the binding did not differ between species. Therefore, neither the acute cellular injury nor glucuronidation-driven irreversible protein binding in vitro is predictive of the drug-induced hepatopathy.


Asunto(s)
Acrilatos/metabolismo , Glucurónidos/metabolismo , Leucotrieno B4/antagonistas & inhibidores , Leucotrieno B4/metabolismo , Hígado/metabolismo , Piridinas/metabolismo , Acrilatos/química , Acrilatos/toxicidad , Adulto , Animales , Perros , Glucurónidos/química , Glucurónidos/toxicidad , Humanos , Técnicas In Vitro , Hígado/efectos de los fármacos , Masculino , Unión Proteica/efectos de los fármacos , Unión Proteica/fisiología , Piridinas/química , Piridinas/toxicidad , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Especificidad de la Especie
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