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1.
Int J Gynaecol Obstet ; 95(3): 236-41, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17010975

RESUMO

Polycystic ovary syndrome is a multi-system endocrinopathy with long-term metabolic and cardiovascular health consequences. Patients typically present due to symptoms of irregular menstruation, hair growth, or infertility; however, recent management options are aimed at further treating underlying glucose-insulin abnormalities as well as androgen excess for proactive control of symptoms. By a 2003 international consensus conference, diagnosis is made by two out of three criteria: chronic oligoovulation or anovulation after excluding secondary causes, clinical or biochemical evidence of hyperandrogenism (but not necessarily hirsutism due to inter-patient variability in hair follicle sensitivity), and radiological evidence of polycystic ovaries. Traditional medical treatment options include oral contraceptive pills, cyclic progestins, ovulation induction, and anti-androgenic medications (aldosterone antagonist, 5alpha-reductase antagonist, and follicle ornithine decarboxylase inhibitor). Recent pharmacotherapies include insulin-sensitizing medications metformin and two thiazolidinediones (rosiglitazone/Avandia and pioglitazone/Actos), a CYP19 aromatase inhibitor (letrozole/Femara), and statins to potentially lower testosterone levels.


Assuntos
Infertilidade Feminina/tratamento farmacológico , Resistência à Insulina/fisiologia , Síndrome do Ovário Policístico/tratamento farmacológico , Acne Vulgar/tratamento farmacológico , Adulto , Clomifeno/uso terapêutico , Antagonistas de Estrogênios/uso terapêutico , Feminino , Hirsutismo/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Síndrome do Ovário Policístico/fisiopatologia
2.
Mol Cell Biol ; 21(24): 8336-45, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11713270

RESUMO

The fucose alpha(1-->2) galactose beta structure is expressed by uterine epithelial cells in the mouse and has been implicated in blastocyst adhesion events thought to be required for murine implantation. Fucalpha(1-->2)Galbeta moieties and cognate fucosyltransferases are also expressed by epithelial cells of the male reproductive tract and have been implicated in sperm maturation events that may contribute to fertilization. To determine directly if Fucalpha(1-->2)Galbeta moieties are required for fertility, we have generated strains of mice that are deficient in genes encoding FUT1 and FUT2, a pair of GDP-L-fucose:beta(1-->4)-D-galactosyl-R 2-alpha-L-fucosyltransferase enzymes (EC 2.4.1.69) responsible for Fucalpha(1-->2)Galbeta synthesis and expression. FUT1 null mice and FUT2 null mice develop normally and exhibit no gross phenotypic abnormalities. The Fucalpha(1-->2)Galbeta epitope is absent from the uterine epithelia of FUT2 null mice and from the epithelia of the epididymis of FUT1 null mice. Fully normal fertility is observed in FUT1 null intercrosses and in FUT2 null intercrosses. These observations indicate that Fucalpha(1-->2)Galbeta moieties are not essential to blastocyst-uterine epithelial cell interactions required for implantation and are not required for sperm maturation events that permit fertilization and that neither the FUT loci nor their cognate fucosylated glycans are essential to normal development.


Assuntos
Fertilidade/genética , Fucosiltransferases/genética , Polissacarídeos/biossíntese , Alelos , Animais , Blastocisto/metabolismo , Southern Blotting , Embrião de Mamíferos/citologia , Epididimo/metabolismo , Células Epiteliais/metabolismo , Feminino , Fertilidade/fisiologia , Fucosiltransferases/fisiologia , Genótipo , Heterozigoto , Homozigoto , Humanos , Imuno-Histoquímica , Lectinas/metabolismo , Masculino , Camundongos , Modelos Genéticos , Mutação , Fases de Leitura Aberta , Fenótipo , Reação em Cadeia da Polimerase , Células-Tronco/metabolismo , Útero/metabolismo , Galactosídeo 2-alfa-L-Fucosiltransferase
3.
Obstet Gynecol Surv ; 56(7): 437-43, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11435952

RESUMO

The initial sequencing of the human genome should be regarded as a milestone in a road that stretches years into the future; the full ramifications of the Human Genome Project are still only being theorized. Researchers will benefit from the catalog of human genes in studies of the genetics of disease susceptibility and the cell biology of gene interactions. Clinicians will increasingly offer genetic or biochemical testing to identify those at highest risk for a number of diseases. Drug discovery will eventually follow newly possible studies of gene expression and protein function. However the Human Genome Project eventually shapes medicine, it is certain that physicians, particularly obstetricians and gynecologists, will need to be well versed in the scientific and ethical issues involved, inasmuch as we will likely be at the center of the most heated debates.


Assuntos
Ética Médica , Predisposição Genética para Doença , Testes Genéticos , Ginecologia/tendências , Projeto Genoma Humano , Obstetrícia/tendências , Comunicação Celular , Feminino , Terapia Genética/tendências , Humanos , Masculino , Gravidez , Diagnóstico Pré-Natal , Fatores de Risco , Análise de Sequência de DNA
4.
J Biol Chem ; 276(26): 23748-56, 2001 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-11323419

RESUMO

Fucosylated oligosaccharides have been proposed to be involved in multiple cell-cell interactions, including mouse blastocyst adhesion and intestine-microbe interactions. To begin to define the regulation and function of terminal alpha(1,2)fucosylated carbohydrates in these and other tissues, we isolated and characterized a 85-kilobase (kb) genomic region of mouse chromosome 7, 23.2 centimorgans analogous to human chromosome 19q13.3 that encodes three alpha(1,2)fucosyltransferases. Gene-specific DNA probes from the open reading frames of the mouse fucosyltransferase genes corresponding to human FUT1, FUT2, and SEC1 demonstrate distinct tissue-specific expression patterns by Northern blot analyses. Flow cytometry profiles of cultured cells transfected with DNA segments containing the open reading frames of the mouse genes confirm that each encodes an alpha(1,2)fucosyltransferase. In uterus and colon, a 3.3-kb FUT2 mRNA represents the major fucosyltransferase gene expressed. Steady-state FUT2 mRNA levels are cyclically regulated during the estrus cycle, increasing 10-fold from early diestrus to a relative maximum in proestrus. In contrast, SEC1 and FUT1 do not show prominently regulated expression in uterus. FUT2 expression localizes to luminal uterine epithelium by in situ hybridization, implying that this gene determines expression of cell surface Fucalpha1-->2Galbeta epitopes proposed to mediate blastocyst adhesion.


Assuntos
Fucosiltransferases/biossíntese , Fucosiltransferases/genética , Útero/metabolismo , Animais , Sequência de Bases , Células COS , Mapeamento Cromossômico , Clonagem Molecular , Colo/metabolismo , Epitélio/metabolismo , Estro/metabolismo , Feminino , Regulação da Expressão Gênica , Genes , Hibridização In Situ , Camundongos , Dados de Sequência Molecular , Fases de Leitura Aberta , RNA Mensageiro/biossíntese , Homologia de Sequência do Ácido Nucleico , Distribuição Tecidual , Galactosídeo 2-alfa-L-Fucosiltransferase
5.
Biochem J ; 327 ( Pt 1): 105-15, 1997 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-9355741

RESUMO

Terminal Fucalpha(1-2)Galbeta epitopes have been proposed to play significant roles in cell-cell interactions in development, cell adhesion, and malignant transformation. To begin to investigate the regulation and function of alpha(1-2)fucosylated epitopes in an animal model, we have isolated and characterized a mouse genomic DNA segment encoding a protein orthologous to the human H blood group locus alpha(1,2)fucosyltransferase (FUT1). This segment maintains an open reading frame encoding 376 amino acids sharing 75% sequence identity with the enzyme encoded by human FUT1, and 55% sequence identity with the enzyme encoded by the human Secretor blood group locus (FUT2). Expression of the open reading frame in COS-7 cells yields an alpha(1,2)fucosyltransferase activity with a Km of 7.6 mM for phenyl-beta-d-galactoside. Southern blotting and interspecific backcross analyses indicate that this murine locus represents a single copy sequence mapping to a novel locus 2.1 centimorgans from the Klk1 locus, in a region of homology between mouse chromosome 7 and the human FUT1 locus on the long arm of chromosome 19. Mouse FUT1 yields a 2.8 kb mRNA transcript identifiable in many organs, including thymus, lung, stomach, pancreas, small intestine, colon, uterus and epidiymis. Hybridization analyses in situ localize expression of FUT1 transcripts to thymic medullary and epididymal epithelial cells, implying that this gene determines the expression of cell surface Fucalpha(1-2)Galbeta epitopes in these tissues.


Assuntos
Mapeamento Cromossômico , Epididimo/enzimologia , Fucosiltransferases/genética , Fucosiltransferases/metabolismo , Timo/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Células COS , Clonagem Molecular , Fucosiltransferases/química , Regulação Enzimológica da Expressão Gênica , Humanos , Hibridização In Situ , Cinética , Masculino , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Especificidade por Substrato , Transfecção , Galactosídeo 2-alfa-L-Fucosiltransferase
6.
Methods Enzymol ; 215: 181-200, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1359387

RESUMO

We have provided a detailed protocol for the synthesis of a yohimbine-agarose matrix that has been shown to be effective for isolation of the alpha 2A-adrenergic receptor from human platelet and purification of the alpha 2A-adrenergic receptor to apparent homogeneity from porcine brain cortex using chromatography on only two sequential yohimbine-agarose columns. In addition, this affinity matrix also interacts with alpha 2 receptors of the alpha 2B subtype extracted from cultured NG108-15 cells. Finally, this affinity matrix has proven useful for monitoring posttranslational modifications of the receptor in digitonin extracts of metabolically labeled cells. Thus, this affinity matrix can be exploited for the purification of multiple alpha 2-adrenergic receptor subtypes on both a macro- and microscale and should be of value to any laboratory exploring the molecular basis for alpha 2-adrenergic functions.


Assuntos
Plaquetas/metabolismo , Receptores Adrenérgicos alfa/isolamento & purificação , Sefarose/análogos & derivados , Ioimbina/análogos & derivados , Agonistas alfa-Adrenérgicos/metabolismo , Fracionamento Celular/métodos , Cromatografia de Afinidade/métodos , Digitonina , Humanos , Indicadores e Reagentes , Ensaio Radioligante/métodos , Receptores Adrenérgicos alfa/análise , Receptores Adrenérgicos alfa/metabolismo , Sefarose/síntese química , Trítio , Ioimbina/sangue , Ioimbina/síntese química
8.
Biol Reprod ; 41(1): 133-41, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2804203

RESUMO

The fucose-sulfate glycoconjugate (FSG) component of sea urchin egg jelly that induces an acrosome reaction in spermatozoa-stimulated multiple Ca2+-dependent phospholipid changes in the sperm cell head and flagellum. When cells were radiolabeled with myo-[3H]inositol, FSG treatment decreased radioactivity in phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate within 30 s. In addition, FSG treatment elevated concentrations of phosphatidic acid in spermatozoa. The Ca2+-channel antagonist, verapamil, inhibited the effects of FSG on [3H]polyphosphoinositides and phosphatidic acid. To investigate the possible compartmentalization of phospholipid turnover, isolated heads and flagella were prepared. Treatment of sperm heads with FSG or the monovalent cation ionophore, gramicidin S, caused increased [3H]inositol phosphate and phosphatidic acid accumulation and induction of an acrosome reaction. Effects of FSG and gramicidin S on phosphatidic acid elevations in sperm heads and intact cells were inhibited by verapamil. FSG failed to cause detectable changes in [3H]inositol phosphate or phosphatidic acid concentrations in isolated flagellar preparations. However, when cells were treated with FSG and the flagella were isolated subsequently, phosphatidic acid concentrations in the flagellar preparations were increased.


Assuntos
Acrossomo/fisiologia , Glicoconjugados/farmacologia , Fosfolipídeos/metabolismo , Ouriços-do-Mar/metabolismo , Cabeça do Espermatozoide/metabolismo , Espermatozoides/metabolismo , Espermatozoides/fisiologia , Sulfatos/farmacologia , Ácidos Sulfúricos , Acrossomo/efeitos dos fármacos , Animais , Separação Celular , Fucose/farmacologia , Fosfatos de Inositol/análise , Fosfatos de Inositol/metabolismo , Masculino , Ácidos Fosfatídicos/análise , Ácidos Fosfatídicos/metabolismo , Fosfatidilinositóis/análise , Fosfatidilinositóis/metabolismo , Fosfolipídeos/análise , Cabeça do Espermatozoide/análise , Cabeça do Espermatozoide/efeitos dos fármacos , Cauda do Espermatozoide/análise , Cauda do Espermatozoide/metabolismo
9.
J Biol Chem ; 264(16): 9412-9, 1989 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-2722841

RESUMO

We report for the first time that phospholipase D activity in sea urchin spermatozoa can be regulated by a component of egg jelly known to induce an acrosome reaction. The fucose-sulfate glycoconjugate (FSG) of egg jelly that induces an acrosome reaction in spermatozoa caused Ca2+-dependent increases in 1,2-diacylglycerol and phosphatidic acid. Diacylglycerol concentrations were increased 2-fold, and phosphatidic acid concentrations were elevated up to 10-fold 2 min after the addition of FSG to spermatozoa. FSG also caused increases in choline, but not in choline phosphate concentrations. Neither phosphorylation of diacylglycerol nor de novo synthesis from glycerol were significant routes of synthesis of phosphatidic acid during the acrosome reaction. When spermatozoa were incubated with FSG in the presence of ethanol, phosphatidylethanol was produced. As ethanol concentrations in the extracellular medium were increased from 0.1 to 2.5%, the amount of phosphatidylethanol increased, whereas phosphatidic acid concentrations decreased, suggesting a competitive transphosphatidylation reaction catalyzed by phospholipase D. Furthermore, when a phosphatidylcholine pool in spermatozoa was radiolabeled using [3H]1-O-alkyl-2-lyso-glycerol-3-phosphorylcholine, the subsequent addition of FSG caused a 4-fold accumulation of [3H]phosphatidic acid. FSG-induced elevations in [3H]phosphatidic acid were positively correlated with the percent of cells that had undergone an acrosome reaction.


Assuntos
Acrossomo/enzimologia , Fucose/fisiologia , Glicoconjugados/fisiologia , Espermatozoides/enzimologia , Sulfatos/fisiologia , Ácidos Sulfúricos , Acrossomo/fisiologia , Animais , Colina/metabolismo , Diglicerídeos/metabolismo , Ativação Enzimática/efeitos dos fármacos , Masculino , Ácidos Fosfatídicos/antagonistas & inibidores , Ácidos Fosfatídicos/biossíntese , Ácidos Fosfatídicos/metabolismo , Fosforilação , Fosforilcolina/metabolismo , Ouriços-do-Mar , Verapamil/farmacologia
10.
J Biol Chem ; 263(2): 690-5, 1988 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-2447081

RESUMO

The hydrolysis of phosphatidylinositol may generate multiple second messengers, including inositol phosphates, 1,2-diacylglycerol, arachidonic acid, and phosphatidic acid. Here, we describe for the first time in spermatozoa that accumulation of one of these potential second messengers, inositol 1,4,5-trisphosphate (1,4,5-IP3), can be stimulated by the fucose-sulfate glycoconjugate (FSG) that induces an acrosome reaction. Sea urchin spermatozoa were labeled with myo-[3H]inositol and incubated with FSG. The amount of [3H]1,4,5-IP3 obtained from FSG-treated cells was up to 10 times that from untreated cells. Increases in the amount of [3H]1,4,5-IP3 were detected within 30 s after addition of FSG (2.5-fold) and were highest at 2 min after addition. Previously, it was shown that FSG induces Ca2+-dependent increases in cyclic AMP concentrations (Kopf, G. S., and Garbers, D. L. (1980) Biol. Reprod. 22, 1118-1126). Increases in [3H]1,4,5-IP3 accumulation caused by FSG were also dependent on extracellular Ca2+. The Ca2+ channel blockers, verapamil and nifedipine, inhibited increases in both [3H]1,4,5-IP3 and cyclic AMP, and the addition of concentrations of extracellular Ca2+ higher than 9.6 mM could reduce the inhibition. When spermatozoa were incubated in Ca2+-free seawater, FSG-induced increases in [3H]1,4,5-IP3 and cyclic AMP concentrations were blocked; addition of extracellular Ca2+ restored the responses. Other treatments that result in the induction of an acrosome reaction, including the addition of monovalent cation H+ exchangers, nigericin and gramicidin S, and incubation in seawater at alkaline pH (pH 8.8), also stimulated accumulation of [3H]1,4,5-IP3 and cyclic AMP.


Assuntos
Acrossomo/efeitos dos fármacos , Fucose/farmacologia , Fosfatos de Inositol/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Fosfatos Açúcares/metabolismo , Animais , Cálcio/metabolismo , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Gramicidina/farmacologia , Inositol 1,4,5-Trifosfato , Masculino , Nifedipino/farmacologia , Nigericina/farmacologia , Ouriços-do-Mar , Verapamil/farmacologia
11.
J Pharmacol Exp Ther ; 243(1): 138-43, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3668847

RESUMO

Plasma morphine levels were measured during abrupt withdrawal in four chronically dependent female monkeys. Approximately 12 hr after withdrawal, the morphine plasma concentrations were about 8 to 10 ng/ml, at which time all of the animals showed mild to moderate symptoms of opiate withdrawal. Severity of withdrawal showed a negative correlation (r = -0.93, P less than .001) with the falling phase of plasma morphine. It may be concluded that, under the conditions of this experiment, significant morphine withdrawal symptoms arose despite measurable plasma concentrations of morphine and that the relationship between plasma concentrations and withdrawal may be quantified according to a linear pharmacokinetic model for a given chronic dose (3.0 mg/kg q 6 hr) of morphine.


Assuntos
Dependência de Morfina/fisiopatologia , Morfina/sangue , Síndrome de Abstinência a Substâncias/fisiopatologia , Animais , Feminino , Cinética , Macaca mulatta , Morfina/farmacocinética , Dependência de Morfina/sangue
12.
Biochem Biophys Res Commun ; 138(2): 728-34, 1986 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-3091021

RESUMO

Spermatozoa from invertebrates (sea urchin, starfish) and vertebrates (trout, guinea pig, bull, pig, human) contain a membrane-bound protein that is ADP-ribosylated by pertussis toxin but not by cholera toxin. The Mr of this protein is 39,000 in invertebrate sperm and 41,000 in mammalian sperm, but 40,000 in trout spermatozoa. The pertussis toxin substrate from sea urchin sperm copurified with [gamma-35S]GTP binding activity. Chymotryptic maps of this ADP-ribosylated protein from sea urchin sperm were the same as those of alpha-subunit of Go from rat brain. Antiserum to the beta-subunit of bovine retinal transducin bound to a sperm protein with Mr approximately 35,000. These studies are the first describing a guanine nucleotide-binding coupling protein in sperm.


Assuntos
Adenosina Difosfato Ribose/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Açúcares de Nucleosídeo Difosfato/metabolismo , Toxina Pertussis , Espermatozoides/metabolismo , Fatores de Virulência de Bordetella/metabolismo , Animais , Bovinos , Membrana Celular/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato) , Guanosina Trifosfato/análogos & derivados , Guanosina Trifosfato/metabolismo , Cobaias , Masculino , Radioisótopos de Fósforo , Ouriços-do-Mar , Especificidade da Espécie , Radioisótopos de Enxofre , Suínos , Tionucleotídeos/metabolismo
13.
Br J Clin Pharmacol ; 21(1): 71-4, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3947506

RESUMO

The time course of toxicity in a 28 year old man following a 100 mg accidental overdose of clonidine hydrochloride is compared with the decline of plasma clonidine over 5 days. The concentration data were analyzed by nonlinear least squares regression, and fitted to a model which dissociated the blood pressure effects into pressor and depressor components. According to this analysis, there appeared to be two phases of toxicity over time--a hypertensive, and a hypotensive phase. The hypotensive and the hypertensive phases may result primarily through differential stimulation of central alpha 2-, alpha 1-, and vascular post-synaptic alpha 2-adrenoceptors as plasma concentrations fall.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Clonidina/sangue , Adulto , Clonidina/intoxicação , Meia-Vida , Humanos , Cinética , Masculino
14.
Clin Pharmacol Ther ; 36(5): 645-53, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6488686

RESUMO

Plasma ketamine concentrations after diazepam and placebo pretreatment were examined in a double-blind, randomized, cross-over study. Eight healthy male subjects received either diazepam or a 0.9% NaCl placebo before ketamine and received the alternate combination 5 to 24 days later. Ten minutes before ketamine dosing, diazepam, 0.3 mg/kg, or placebo in equal volume was injected intravenously at a rate not exceeding 5 mg/min. Ketamine, 2.2 mg/kg iv, was injected over 1 min. For the clinically relevant period for anesthesia (1 to 30 min), diazepam-ketamine treatment resulted in higher plasma levels at most time points, but diazepam pretreatment did not alter plasma levels of metabolite KI and pseudometabolite KII nor the 24-hr urinary excretion of ketamine, KI, and KII. Ketamine kinetics followed a three-term exponential decline under both treatment conditions. After placebo-ketamine dosing, plasma t 1/2s were as follows: distribution (pi t 1/2) = 24.1 sec, redistribution (alpha t 1/2) = 4.68 min, and elimination (beta t 1/2) = 2.17 hr. After diazepam-ketamine dosing, t 1/2s were: pi t 1/2 = 25.0 sec, alpha t 1/2 6.37 min, and beta t 1/2 = 2.32 hr.


Assuntos
Anestesia , Diazepam/farmacologia , Ketamina/metabolismo , Adulto , Análise de Variância , Relação Dose-Resposta a Droga , Método Duplo-Cego , Interações Medicamentosas , Humanos , Injeções Intravenosas , Ketamina/sangue , Cinética , Masculino , Distribuição Aleatória , Sono/efeitos dos fármacos
18.
Anesth Analg ; 61(2): 87-92, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7198883

RESUMO

Ketamine and two of its metabolites were determined up to 24 hours by a sensitive and specific gas chromatographic mass fragmentographic (GCMF) assay in the plasma of seven premedicated surgical patients. Each patient received ketamine in a dose between 2.0 and 2.2 mg/kg given intravenously over a 30-second period. Plasma levels of ketamine varied from 9,000 to 25,800 ng/ml 1 minute after injection to approximately 1,000 ng/ml when the patients began to recover consciousness. Within the next 24 hours, the patients had a complex logarithmic decline after injection. The data suggest rather complex pharmacokinetics with multiple compartments. Ketamine metabolites I and II were also found in the plasma over comparable periods of time. Ketamine metabolite I levels ranged from a high of 245 to 668 ng/ml within 30 minutes after ketamine administration to as low as 15 ng/ml 24 hours later. Ketamine metabolite II levels were lower with a peak of 515 ng/ml in approximately 60 minutes to 13 to 27 ng/ml 24 hours later. Recovery from anesthesia was related to the first two phases of rapid redistribution of ketamine. The plasma levels of the two ketamine metabolites were first detectable approximately 5 minutes after ketamine injection. Their relatively low levels throughout ketamine anesthesia and postanesthesia do not correlate with recovery from anesthesia. CSTRIP and NONLIN analysis indicated that a three-exponential equation best approximated the data obtained. It is concluded that a three-compartment open model best approximates ketamine pharmacokinetics in these patients.


Assuntos
Ketamina/sangue , Adulto , Computadores , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Procedimentos Cirúrgicos Operatórios
19.
Subst Alcohol Actions Misuse ; 3(4): 205-11, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7167862

RESUMO

A pharmacokinetic analysis comparing a 2 and 3 compartment model was performed on the published data of Wall et al. (12) on the kinetics of phencyclidine (PCP). These investigators gave 100 micrograms (mean 1.3 micrograms/kg) of 3H-PCP i.v. to three human volunteers and followed the plasma disappearance of PCP over 72 hr. They suggested that PCP followed a 2 compartment model with a plasma half life of 7-16 hr. In the present analysis, additional pharmacokinetic estimations from the plasma data were made and a 3 compartment model developed. The results obtained suggest complex PCP kinetics involving an initial pi half life of 5.5 min, an alpha half life of 4.6 hr, and a beta half life of 22 hr. The volume of distribution was large, varying from 2.2 to 2.4 1/kg for each compartment, suggesting binding of PCP.


Assuntos
Fenciclidina/sangue , Meia-Vida , Humanos , Cinética , Taxa de Depuração Metabólica
20.
J Anal Toxicol ; 4(6): 299-304, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6259446

RESUMO

The polybrominated biphenyl (PBB) constituents of Firemaster FF-1 were determined using gas chromatography-electron capture (GC-EC). The absolute and relative retention times of each of eight major constituents were obtained. It was shown that 2,2',5,5'-tetrabromobiphenyl was a suitable internal standard for the quantitative analysis of the PBBs in Firemaster FF-1 in mammalian tissues and fluids.


Assuntos
Compostos de Bifenilo/análise , Retardadores de Chama/análise , Bifenil Polibromatos/análise , Cromatografia Gasosa/métodos
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