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1.
Phytomedicine ; 22(1): 158-64, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25636885

RESUMO

AIMS: To determine if the phytotherapeutic agent, Bryophyllum pinnatum, could serve as an alternative drug for the overactive bladder syndrome, and to characterise the fraction responsible for the inhibition of detrusor contractility. METHODS: Fractions were prepared from the MeOH extract of B. pinnatum and further analysed by HPLC-PDA-MS. Detrusor muscle strips were prepared from porcine bladders and the electrically induced muscle contractility measured by organ bath. The effect of B. pinnatum leaf press juice (2.5-10%), a flavonoid fraction (0.1-1 mg/ml), and a bufadienolide fraction (0.1-40 µg/ml) on detrusor contractility was assessed and compared with controls (polar fraction (0.5-5 mg/ml) and oxybutynin (10(-8)-10(-6) M)). RESULTS: The press juice, at a concentration of 10% led to a reduction of detrusor contractility. Bladder strips treated with the flavonoid fraction showed a significant reduction of the contractility to 21.3 ± 5.2% (1 mg/ml) while the bufadienolide fraction had no inhibitory effect in the investigated concentrations. The polar fraction showed a reduction of the contractility in a pH-dependent fashion. At 10(-6) M concentration oxybutynin reduced the detrusor contractility to 21.9 ± 4.7%. CONCLUSIONS: The flavonoid fraction of Bryophyllum pinnatum reduces the porcine detrusor contractility in a dose- and time-dependent manner. Fractions from B. pinnatum may be a new pharmacological approach for the treatment of OAB.


Assuntos
Flavonoides/farmacologia , Kalanchoe/química , Contração Muscular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Bufanolídeos/farmacologia , Feminino , Técnicas In Vitro , Estrutura Molecular , Músculo Liso/efeitos dos fármacos , Fitoterapia , Folhas de Planta/química , Suínos , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária Hiperativa/tratamento farmacológico
2.
Phytomedicine ; 19(10): 947-51, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22824522

RESUMO

AIMS: A broad spectrum of synthetic agents is available for the treatment of overactive bladder. Anti-cholinergic drugs show a poor compliance due to side effects. There is an increasing use of plant extracts in medicine. We have therefore investigated the inhibitory effects of leaf press juice from Bryophyllum pinnatum (Lam.) Oken (Kalanchoe pinnata L.) on bladder strips and compared the effects to that of oxybutynin. METHODS: Strips of porcine detrusor were prepared in Krebs solution and contractility was measured in a myograph system chamber aired with O2/CO2 at 37 °C. To induce contractions, electrical field stimulation (32 Hz, 40 V) was used for the inhibitory effect measurements, and carbachol (50 µM) for the relaxant effect measurements. Recordings were obtained in the absence and presence of increasing concentrations of Bryophyllum pinnatum leaf press juice (BPJ, 0.1-10%), and oxybutynin (10⁻7-10⁻³ M) as a reference substance. RESULTS: In inhibition experiments, BPJ as well as oxybutynin inhibited electrically induced contractions of porcine detrusor. BPJ at concentrations of 5% inhibited the contraction compared to a time matched control significantly by 74.6±10.2% (p<0.001). BPJ as well as oxybutynin relaxed carbachol pre-contracted porcine detrusor strips. The maximum relaxant effect of BPJ compared to a time matched control was 18.7±3.7 (p<0.05) at a concentration of 10% BPJ. CONCLUSIONS: Our investigations show that BPJ inhibits contractions induced by electrical field stimulation and relaxes carbachol-induced contractions. However, the effect was lower than that of the reference substance oxybutynin. It is important to continue in vitro experiments as well as clinical studies with BPJ that might offer a new treatment option for patients with OAB.


Assuntos
Kalanchoe , Ácidos Mandélicos/uso terapêutico , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Parassimpatolíticos/uso terapêutico , Bexiga Urinária Hiperativa , Bexiga Urinária/efeitos dos fármacos , Animais , Carbacol/farmacologia , Agonistas Colinérgicos/farmacologia , Estimulação Elétrica , Ácidos Mandélicos/farmacologia , Antagonistas Muscarínicos/farmacologia , Antagonistas Muscarínicos/uso terapêutico , Músculo Liso/fisiologia , Parassimpatolíticos/farmacologia , Fitoterapia , Folhas de Planta , Preparações de Plantas/farmacologia , Preparações de Plantas/uso terapêutico , Suínos , Bexiga Urinária/fisiologia , Bexiga Urinária Hiperativa/tratamento farmacológico
4.
Phytomedicine ; 19(1): 74-82, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21802930

RESUMO

AIMS: The use of preparations from Bryophyllum pinnatum (Lamarck) Oken (Kalanchoe pinnata (Lamarck) Persoon) in tocolysis is supported by clinical evidence. We studied here the effect of B. pinnatum leaf press juice and its chemical fractions on the response of human myometrial strips. No data are available if the influence on myometrial strips of the juice differs from that of its components in the chemical fractions, in order to increase the pharmacological effect. METHODOLOGY: In vitro study to test the effect of repeated addition of B. pinnatum leaf press juice (BPJ) and its chemical components in several dilutions (undiluted, 1-10%) on myometrium strips hang up in a myograph chamber. Chemical analysis is including HPLC, MPLC with Sephadex LH-20 and TLC. RESULTS: All test solutions are inhibiting contractility by reducing the amplitude and the area under the curve (AUC) of the contractions. Undiluted BPJ and its undiluted chemical fraction 4 are reducing most effective these two parameters: the amplitude was at 78% of the baseline (95% CI (77-89); p<0.05) at the second addition of the BPJ and at 70% (95% CI (50-90); p<0.05) of the first addition of fraction 4; the AUC was at 82% (95% CI (69-95); p<0.05) of the baseline at the first addition of the press juice and at 51% (95% CI (27-74); p<0.05) at the first addition of fraction 4. The BPJ decreased amplitude and AUC significantly faster and increased frequency significantly faster than the control. Fractions could be tentatively assigned to bufadienolids, flavonoids and cinnamic acids. Fraction 4, accounted for flavonoids, increased the frequency of the contractions most effectively: 557% of the baseline (95% CI (316-797); p<0.05) at the first addition. CONCLUSION: Leaf juice of B. pinnatum and its flavonoid fraction are most effective in relaxing myometrial strips by inducing frequency.


Assuntos
Flavonoides/farmacologia , Kalanchoe/química , Miométrio/efeitos dos fármacos , Contração Uterina/efeitos dos fármacos , Feminino , Humanos , Técnicas In Vitro , Extratos Vegetais/farmacologia , Folhas de Planta/química , Gravidez , Tocólise
5.
Clin Pharmacol Ther ; 90(2): 246-55, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21677639

RESUMO

This study assessed the pharmacodynamic and pharmacokinetic effects of the interaction between the selective norepinephrine (NE) transporter inhibitor reboxetine and 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") in 16 healthy subjects. The study used a double-blind, placebo-controlled crossover design. Reboxetine reduced the effects of MDMA including elevations in plasma levels of NE, increases in blood pressure and heart rate, subjective drug high, stimulation, and emotional excitation. These effects were evident despite an increase in the concentrations of MDMA and its active metabolite 3,4-methylenedioxyamphetamine (MDA) in plasma. The results demonstrate that transporter-mediated NE release has a critical role in the cardiovascular and stimulant-like effects of MDMA in humans.


Assuntos
Inibidores da Captação Adrenérgica/farmacologia , Morfolinas/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Norepinefrina/sangue , 3,4-Metilenodioxianfetamina/farmacocinética , Adulto , Pressão Sanguínea/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Interações Medicamentosas , Feminino , Alucinógenos/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Norepinefrina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/antagonistas & inibidores , Reboxetina , Adulto Jovem
6.
Phytomedicine ; 17(12): 980-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20381326

RESUMO

The use of preparations from Bryophyllum pinnatum in tocolysis is supported by both clinical (retrospective comparative studies) and experimental (using uterus strips) evidence. We studied here the effect of B. pinnatum juice on the response of cultured human myometrial cells to stimulation by oxytocin, a hormone known to be involved in the control of uterine contractions by increasing the intracellular free calcium concentration ([Ca2+]i). In this work, [Ca2+]i was measured online during stimulation of human myometrial cells (hTERT-C3 and M11) with oxytocin, which had been pre-incubated in the absence or in the presence of B. pinnatum juice. Since no functional voltage-gated Ca2+ channels could be detected in these myometrial cells, the effect of B. pinnatum juice was as well studied in SH-SY5Y neuroblastoma cells, which are known to have such channels and can be depolarised with KCl. B. pinnatum juice prevented the oxytocin-induced increase in [Ca2+]i in hTERT-C3 human myometrial cells in a dose-dependent manner, achieving a ca. 80% inhibition at a 2% concentration. Comparable results were obtained with M11 human primary myometrial cells. In hTERT-C3 cells, prevention of the oxytocin-induced increase in [Ca2+]i was independent of the extracellular Ca2+ concentration and of voltage-dependent Ca2+-channels. B. pinnatum juice delayed, but did not prevent the depolarization-induced increase in [Ca2+]i in SH-SY5Y cells. Taken together, the data suggest a specific and concentration-dependent effect of B. pinnatum juice on the oxytocin signalling pathway, which seems to corroborate its use in tocolysis. Such a specific mechanism would explain the rare and minor side-effects in tocolysis with B. pinnatum as well as its high therapeutic index.


Assuntos
Canais de Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Kalanchoe , Miométrio/efeitos dos fármacos , Preparações de Plantas/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Feminino , Humanos , Miométrio/metabolismo , Neuroblastoma , Ocitocina/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Aliment Pharmacol Ther ; 28(11-12): 1334-41, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18808445

RESUMO

BACKGROUND: Constipation is a significant side effect of opioid therapy. We have previously demonstrated that naloxone-3-glucuronide (NX3G) antagonizes the motility-lowering-effect of morphine in the rat colon. AIM: To find out whether oral NX3G is able to reduce the morphine-induced delay in colonic transit time (CTT) without being absorbed and influencing the analgesic effect. METHODS: Fifteen male volunteers were included. Pharmacokinetics: after oral administration of 0.16 mg/kg NX3G, blood samples were collected over a 6-h period. Pharmacodynamics: NX3G or placebo was then given at the start time and every 4 h thereafter. Morphine (0.05 mg/kg) or placebo was injected s.c. 2 h after starting and thereafter every 6 h for 24 h. CTT was measured over a 48-h period by scintigraphy. Pressure pain threshold tests were performed. RESULTS: Neither NX3G nor naloxone was detected in the venous blood. The slowest transit time was observed during the morphine phase, which was significantly different from morphine with NX3G and placebo. The pain perception was not significantly influenced by NX3G. CONCLUSIONS: Orally administered NX3G is able to reverse the morphine-induced delay of CTT in humans without being detected in peripheral blood samples. Therefore, NX3G may improve symptoms of constipation in-patients using opioid medication without affecting opioid-analgesic effects.


Assuntos
Colo/efeitos dos fármacos , Colo/fisiologia , Naloxona/análogos & derivados , Antagonistas de Entorpecentes/farmacologia , Adulto , Analgésicos Opioides/efeitos adversos , Colo/diagnóstico por imagem , Estudos Cross-Over , Método Duplo-Cego , Trânsito Gastrointestinal/efeitos dos fármacos , Humanos , Radioisótopos de Índio , Masculino , Morfina/efeitos adversos , Naloxona/sangue , Naloxona/farmacocinética , Naloxona/farmacologia , Antagonistas de Entorpecentes/sangue , Antagonistas de Entorpecentes/farmacocinética , Cintilografia , Limiar Sensorial/efeitos dos fármacos , Adulto Jovem
8.
Spinal Cord ; 45(8): 551-62, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17043680

RESUMO

STUDY DESIGN: Open label study to determine drug dose for a randomized double-blind placebo-controlled parallel study. OBJECTIVES: To assess the efficacy and side effects of oral Delta(9)-tetrahydrocannabinol (THC) and rectal THC-hemisuccinate (THC-HS) in SCI patients. SETTING: REHAB Basel, Switzerland. METHOD: Twenty-five patients with SCI were included in this three-phase study with individual dose adjustment, each consisting of 6 weeks. Twenty-two participants received oral THC open label starting with a single dose of 10 mg (Phase 1, completed by 15 patients). Eight subjects received rectal THC-HS (Phase 2, completed by seven patients). In Phase 3, six patients were treated with oral THC and seven with placebo. Major outcome parameters were the spasticity sum score (SSS) using the Modified Ashworth Scale (MAS) and self-ratings of spasticity. RESULTS: Mean daily doses were 31 mg with THC and 43 mg with THC-HS. Mean SSS for THC decreased significantly from 16.72 (+/-7.60) at baseline to 8.92 (+/-7.14) on day 43. Similar improvement was seen with THC-HS. We observed a significant improvement of SSS with active drug (P=0.001) in the seven subjects who received oral THC in Phase 1 and placebo in Phase 3. Major reasons for drop out were increase of pain and psychological side effects. CONCLUSION: THC is an effective and safe drug in the treatment of spasticity. At least 15-20 mg per day were needed to achieve a therapeutic effect.


Assuntos
Dronabinol/uso terapêutico , Espasticidade Muscular/tratamento farmacológico , Espasticidade Muscular/etiologia , Traumatismos da Medula Espinal/complicações , Administração Oral , Administração Retal , Adulto , Afeto , Idoso , Atenção , Relação Dose-Resposta a Droga , Método Duplo-Cego , Dronabinol/administração & dosagem , Dronabinol/efeitos adversos , Teste de Esforço , Feminino , Humanos , Pulmão/fisiopatologia , Masculino , Manometria , Pessoa de Meia-Idade , Espasticidade Muscular/fisiopatologia , Espasticidade Muscular/psicologia , Testes Neuropsicológicos , Dor/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/psicologia , Resultado do Tratamento , Bexiga Urinária/fisiopatologia
9.
Neurogastroenterol Motil ; 14(5): 487-93, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12358676

RESUMO

There is considerable evidence that opioid mechanisms are involved in the mediation of pyloric motor responses that in turn regulate gastric emptying. The purpose of this randomized, placebo-controlled crossover study was to investigate the effect of naloxone on gastric emptying of a solid meal, gastric myoelectrical activity and the postprandial release of gastrointestinal peptides and neuropeptides in 20 healthy volunteers. Naloxone was administered as an intravenous bolus, followed by continuous infusion according to an intravenous dosing nomogram. Gastric emptying time was evaluated by scintigraphy and gastric myoelectrical activity was evaluated by cutaneous electrogastrography. Naloxone did not significantly alter gastric half-emptying time and postprandial dominant gastric electrical frequency compared with placebo. It also did not significantly change the plasma levels of several peptide hormones with the exception of neuropeptide Y, which was significantly increased (P = 0.001). In conclusion, in doses that influence human intestinal motility, naloxone had no effect on gastric motility and release of several peptide hormones in healthy male volunteers. The importance of the isolated increased neuropeptide Y plasma level needs further investigation.


Assuntos
Esvaziamento Gástrico/efeitos dos fármacos , Hormônios Gastrointestinais/sangue , Complexo Mioelétrico Migratório/efeitos dos fármacos , Naloxona/farmacologia , Adulto , Estudos Cross-Over , Esvaziamento Gástrico/fisiologia , Humanos , Masculino , Complexo Mioelétrico Migratório/fisiologia , Período Pós-Prandial/efeitos dos fármacos , Período Pós-Prandial/fisiologia , Estudos Prospectivos , Estatísticas não Paramétricas
10.
J Anal Toxicol ; 25(4): 258-69, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11386639

RESUMO

The abuse of the designer amphetamines such as 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy) is increasing throughout the world. They have become popular drugs, especially at all-night techno dance parties (Raves), and their detection is becoming an important issue. Presently, there are no MDMA- or MDA-specific immunoassays on the market, and detection of the designer amphetamines is dependent upon the use of commercially available amphetamine assays. The success of this approach has been difficult to assess because of the general unavailability of significant numbers of samples from known drug users. The objectives of the present study are to characterize the drug content of urine samples from admitted Ecstasy users by chromatographic methods and to assess the ability of the available amphetamine/methamphetamine immunoassays to detect methylenedioxyamphetamines. We found that, when analyzed by high-performance liquid chromatography with diode-array detection (HPLC-DAD), 64% of 70 urine samples (by gas chromatography-mass spectrometry [GC-MS]: 88% of 64 urine samples) obtained from Rave attendees contained MDMA and/or 3,4-methylenedioxyamphetamine (MDA) alone or in combination with amphetamine, methamphetamine, or other designer amphetamines such as 3,4-methylenedioxyethylamphetamine (MDEA). This suggests that the majority of the Ravers are multidrug users. At the manufacturer's suggested cutoffs, the Abbott TDx Amphetamine/Methamphetamine II and the new Roche HS Amphetamine/MDMA assays demonstrated greater detection sensitivity for MDMA than the other amphetamine immunoassays tested (Abuscreen OnLine Hitachi AMPS, Abuscreen OnLine Integra AMPS, Abuscreen OnLine Integra AMPSX, CEDIA AMPS, and EMIT II AMPS). There is 100% agreement between each of the two immunoassays with the reference chromatographic methods, HPLC-DAD and GC-MS, for the detection of methylenedioxyamphetamines.


Assuntos
Estimulantes do Sistema Nervoso Central/urina , Alucinógenos/urina , Drogas Ilícitas/urina , Imunoensaio/métodos , N-Metil-3,4-Metilenodioxianfetamina/urina , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Alucinógenos/química , Alucinógenos/toxicidade , Humanos , Drogas Ilícitas/química , Drogas Ilícitas/toxicidade , N-Metil-3,4-Metilenodioxianfetamina/química , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Sensibilidade e Especificidade , Detecção do Abuso de Substâncias/métodos
11.
J Anal Toxicol ; 25(8): 699-704, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11765027

RESUMO

A clinical study was conducted to assess the ability of commercially available immunoassays to detect flunitrazepam (FNP) in plasma and urine samples and to compare the results with those obtained by gas chromatography-mass spectrometry (GC-MS). The clinical study consisted of four individuals (two male and two female) who had taken a single 2-mg dose of FNP. Serum was collected over a 48-h period and urine was collected over a 72-h period. The serum and urine samples were analyzed by the COBAS INTEGRA Serum Benzodiazepines assay (SBENZ), the TDx serum and urine Benzodiazepines assay, and GC-MS. The GC-MS procedure was developed for analysis of FNP and metabolites in plasma and urine using an acid hydrolysis step resulting in the formation of specific benzophenones corresponding to FNP and its metabolites. The relative sensitivities of the assays for the detection of FNP and metabolites in serum and urine were GC-MS > SBENZ > TDx. The immunoassay results for serum samples showed peak concentrations of FNP metabolites at 8 h after FNP ingestion for three individuals and at about 1 h for the fourth individual. The GC-MS, SBENZ, and TDx urine immunoassays detected drug above the stated limit of detection (LOD) in 44, 41, and 35 serial FNP urine samples, respectively. FNP metabolites were detected in urine samples with all three assays for up to 72 h after a 2-mg dose. The improved detection rate with the SBENZ assay as compared to the TDx assay is likely explained by its higher cross-reactivity with the major metabolite, 7-amino-flunitrazepam (7-amino-FNP), and its lower LOD.


Assuntos
Ansiolíticos/sangue , Ansiolíticos/urina , Flunitrazepam/análogos & derivados , Flunitrazepam/sangue , Flunitrazepam/urina , Imunoensaio/normas , Administração Oral , Adulto , Ansiolíticos/metabolismo , Feminino , Flunitrazepam/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Sensibilidade e Especificidade , Detecção do Abuso de Substâncias
12.
Int J Clin Pharmacol Ther ; 38(10): 486-91, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11073290

RESUMO

OBJECTIVE: The pharmacokinetics and pharmacodynamics of high-dose intravenous (i.v.), oral and rectal diacetylmorphine (diamorphine, heroin, DAM) preparations were compared. METHOD: Two heroin-dependent patients participating in a heroin-assisted treatment program received single or repeated doses of 200 - 690 mg DAM i.v., orally (capsules, controlled-release tablets) and rectally. Plasma and urine profiles of DAM and metabolites were monitored by high-performance liquid chromatography and gas chromatography mass spectrometry, flash and high effects by visual analog scaling (VAS). RESULTS: DAM was only detectable in plasma after i.v. administration. With a t 1/2 beta of 1.3 - 2.2 min it was rapidly desacetylated to 6-acetylmorphine which was further metabolized to morphine and its 3- and 6-O-glucuronide. Morphine-3-glucuronide was the dominating metabolite in plasma and urine independent of the administration route. Oral and rectal doses and dosage intervals were adequate to produce flash and high effects without any cardiovascular and respiratory side-effects nor withdrawal symptoms. CONCLUSIONS: Oral and rectal DAM should further be tested and validated on a wider patient group for the non-invasive, long-term application of high-dose DAM within heroin-assisted treatment programs as alternative to the harmful i.v. application.


Assuntos
Heroína/farmacologia , Heroína/farmacocinética , Transtornos Relacionados ao Uso de Opioides/etiologia , Administração Oral , Adulto , Feminino , Heroína/administração & dosagem , Dependência de Heroína/terapia , Humanos , Injeções Intravenosas , Masculino , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Projetos Piloto , Supositórios
13.
Br J Anaesth ; 84(1): 97-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10740556

RESUMO

The pharmacodynamics of morphine-6-glucuronide (M-6-G) i.v. were assessed in 12 healthy male volunteers in an open study. After a single bolus dose of M-6-G 5 mg i.v., we measured antinociceptive effects, using electrical and cold pain tests, and plasma concentrations of M-6-G, morphine-3-glucuronide (M-3-G) and morphine. Pain intensities during electrical stimulation (at 30, 60 and 90 min after injection) and ice water immersion (at 60 min) decreased significantly (P < 0.005) compared with baseline. Mean plasma peak concentrations of M-6-G were 139.3 (SD 38.9) ng ml-1, measured at 15 min. Our data demonstrate that M-6-G has significant analgesic activity.


Assuntos
Analgésicos Opioides/uso terapêutico , Derivados da Morfina/uso terapêutico , Dor Pós-Operatória/prevenção & controle , Adulto , Analgésicos Opioides/sangue , Temperatura Baixa , Estimulação Elétrica , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Derivados da Morfina/sangue , Medição da Dor
14.
Br J Clin Pharmacol ; 49(2): 104-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10671903

RESUMO

AIMS: 3,4-Methylenedioxymethamphetamine (MDMA, commonly called ecstasy) is a synthetic compound increasingly popular as a recreational drug. Little is known about its pharmacology, including its metabolism and pharmacokinetics, in humans in controlled settings. A clinical trial was designed for the evaluation of MDMA pharmacological effects and pharmacokinetics in healthy volunteers. METHODS: A total of 14 subjects were included. In the pilot phase six received MDMA at 50 (n=2), 100 (n=2), and 150 mg (n=2). In the second phase eight received MDMA at both 75 and 125 mg (n=8). Subjects were phenotyped for CYP2D6 activity and were classified as extensive metabolizers for substrates, such as MDMA, whose hepatic metabolism is regulated by this enzyme. Plasma and urine samples were collected throughout the study for the evaluation of MDMA pharmacokinetics. Body fluids were analysed for the determination of MDMA and its main metabolites 3,4-methylenedioxyamphetamine (MDA), 4-hydroxy-3-methoxy-methamphetamine (HMMA) and 4-hydroxy-3-methoxy-amphetamine (HMA). RESULTS: As the dose of MDMA administered was increased, volunteers showed rises in MDMA concentrations that did not follow the same proportionality which could be indicative of nonlinearity. In the full range of doses tested the constant recovery of HMMA in the urine combined with the increasing MDMA recovery seems to point towards a saturation or an inhibition of MDMA metabolism (the demethylenation step). These observations are further supported by the fact that urinary clearance was rather constant while nonrenal clearance was dose dependent. CONCLUSIONS: It has previously been postulated that individuals genetically deficient for the hepatic enzyme CYP2D6 (about 10% of the Caucasian people) were at risk of developing acute toxicity at moderate doses of MDMA because the drug would accumulate in the body instead of being metabolized and inactivated. The lack of linearity of MDMA pharmacokinetics (in a window of doses compatible with its recreational use) is a more general phenomenon as it concerns the whole population independent of their CYP2D6 genotype. It implies that relatively small increases in the dose of MDMA ingested are translated to disproportionate rises in MDMA plasma concentrations and hence subjects are more prone to develop acute toxicity.


Assuntos
Alucinógenos/farmacocinética , N-Metil-3,4-Metilenodioxianfetamina/farmacocinética , 3,4-Metilenodioxianfetamina/urina , Adulto , Área Sob a Curva , Pressão Sanguínea/efeitos dos fármacos , Estudos Cross-Over , Desoxiepinefrina/análogos & derivados , Desoxiepinefrina/urina , Diástole , Relação Dose-Resposta a Droga , Método Duplo-Cego , Alucinógenos/sangue , Alucinógenos/urina , Humanos , Concentração de Íons de Hidrogênio , Masculino , Taxa de Depuração Metabólica , Metanfetamina/análogos & derivados , Metanfetamina/urina , N-Metil-3,4-Metilenodioxianfetamina/sangue , N-Metil-3,4-Metilenodioxianfetamina/urina , Projetos Piloto , Fatores de Tempo
15.
J Anal Toxicol ; 23(6): 486-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10517555

RESUMO

A gas chromatography-mass spectrometry method was developed for the analysis of flunitrazepam (FN) and its major metabolite, 7-amino-flunitrazepam (7-amino-FN), in both plasma and whole blood. The method was based on acid hydrolysis of the samples after dilution with HPLC water followed by extraction and derivatization (heptafluorobutyrate) of the resulting benzophenones. Analysis of plasma and whole blood samples from subjects administered 2-mg doses of FN showed that FN was only detected in whole blood (LOD 5 ng/mL) and not in plasma. However, 7-amino-FN was detected in both plasma and whole blood, although the levels were much higher in plasma. 7-Amino-FN was detected for the entire period of specimen collection (12 h), but FN was only detected in whole blood for 4 h after ingestion with peak levels after 1 h.


Assuntos
Ansiolíticos/sangue , Benzofenonas/análise , Flunitrazepam/análogos & derivados , Flunitrazepam/sangue , Detecção do Abuso de Substâncias/métodos , Flunitrazepam/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidrólise , Fatores de Tempo
16.
J Chromatogr B Biomed Sci Appl ; 723(1-2): 221-32, 1999 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-10080649

RESUMO

A gas chromatographic method with nitrogen-phosphorus detection involving a solid-liquid extraction phase was developed and validated for the simultaneous quantification of 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA) in plasma. A modification of this method was validated for the analysis of MDMA, MDA, 4-hydroxy-3-methoxymethamphetamine (HMMA) and, 4-hydroxy-3-methoxyamphetamine (HMA) in urine. Under the analytical conditions described, the limits of detection in plasma and urine were less than 1.6 microg/l and 47 microg/l, respectively, for all the compounds studied. Good linearity was observed in the concentration range evaluated in plasma (5-400 microg/l) and urine (100-2000 microg/l) for all compounds tested. The recoveries obtained from plasma were 85.1% and 91.6% for MDMA and MDA, respectively. Urine recoveries were higher than 90% for MDMA and MDA, 74% for HMMA, and 64% for HMA. Methods have been successfully used in the assessment of plasma and urine concentrations of MDMA and its main metabolites in samples from clinical studies in healthy volunteers.


Assuntos
Cromatografia Gasosa/métodos , N-Metil-3,4-Metilenodioxianfetamina/metabolismo , Humanos , Masculino , N-Metil-3,4-Metilenodioxianfetamina/sangue , N-Metil-3,4-Metilenodioxianfetamina/urina , Nitrogênio , Fósforo , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
J Anal Toxicol ; 22(6): 425-9, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9788516

RESUMO

In addition to acetylmorphine (6-AM), acetylcodeine (AC) has been suggested as a marker for the use of illicit heroin. Because no procedure was available for AC testing in hair, a new method was developed for the simultaneous identification and quantitation of morphine (MOR), codeine (COD), 6-AM, and AC. After decontamination, each hair specimen was cut into 1-mm pieces. A 50-mg aliquot was incubated overnight at 50 degrees C in 1 mL Soerensen buffer (pH 7.6) in presence of 200 ng of MOR-d3, COD-d3, 6-AM-d3, and AC-d3. After pH adjustment to 8.4, the analytes were extracted in 5 mL of chloroform/isopropanol/n-heptane (25:10:65, v/v/v). The organic phase was removed and evaporated to dryness, and the residue was derivatized by silylation (BSTFA + 1% TMCS). Drugs were analyzed by gas chromatography-mass spectrometry in electron impact mode. Limits of quantitation were set to 0.1 ng/mg. Fifty hair specimens obtained from subjects who died from fatal opiate overdose were analyzed. AC was detected in 22 samples in concentrations ranging from 0.17 to 5.60 ng/mg with a mean value of 1.04 ng/mg. 6-AM was also present in these samples at concentrations ranging from 1.35 to 41.10 ng/mg with a mean value of 7.79 ng/mg. Of the 28 specimens negative for AC, 21 were positive for 6-AM at concentrations ranging from 0.18 to 7.13 ng/mg. When detected, the AC concentrations were an average of 15.5% (2.8 to 32.6%) of the 6-AM concentrations. There was a positive relationship between AC concentrations and 6-AM concentrations (r = 0.915, p = 0.001). Neither AC nor COD was identified in hair specimens collected from 20 subjects taking part in a heroin-maintenance program in Switzerland and receiving pure pharmaceutical heroin hydrochloride daily. Although it is indicative of illicit heroin use, AC would not make a suitable biomarker in place of 6-AM because of its low concentration in hair compared with that of 6-AM and its absence in about 50% of the specimens that tested positive for 6-AM.


Assuntos
Codeína/análogos & derivados , Cabelo/química , Dependência de Heroína , Heroína/análise , Entorpecentes/análise , Detecção do Abuso de Substâncias/métodos , Biomarcadores , Codeína/análise , Cromatografia Gasosa-Espectrometria de Massas , Heroína/uso terapêutico , Dependência de Heroína/reabilitação , Humanos , Morfina/análise , Derivados da Morfina/análise , Entorpecentes/uso terapêutico
18.
J Anal Toxicol ; 22(3): 231-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9602941

RESUMO

Hair specimens were collected from the vertex area of 20 subjects taking part in a heroin-maintenance program. Subjects were administered, under controlled conditions, heroin hydrochloride in 2 or 3 doses/day intravenously. Heroin doses ranged from 30 to 800 mg/day, and were self-administered. In all cases, a 4-cm segment from the proximal zone (root) was analyzed, which corresponded to about 100 days of hair growth. During that period, total heroin administered ranged from 14,100 to 71,540 mg. All special features of hair such as coloring, bleaching, etc. were noted. Each sample was washed twice with dichloromethane (5 mL, 2 min) and, after drying, cut into small pieces of approximately 1 mm. A 30-35-mg aliquot was incubated overnight at 45 degrees C in 1 mL methanol in the presence of 200 ng of heroin-d9, 6-acetylmorphine-d3, and morphine-d3. The methanolic extract was then evaporated to dryness, and the residue was derivatized by silylation (BSTFA + 1% TMCS). Drugs were analyzed by gas chromatography-mass spectrometry in electron impact mode. Limits of quantitation were set to 0.1 ng/mg. Concentrations ranged from 0 to 4.53, 0.38 to 10.11, and 0.71 to 5.20 ng/mg for heroin, 6-acetylmorphine, and morphine, respectively. 6-Acetylmorphine was the major analyte present in hair in all but five cases. Heroin was present in the highest concentration in three cases, and morphine was the major metabolite in two cases, probably because of hydrolysis. Subjects tested positive for heroin in all but two cases. No correlation between the doses of administered heroin and the concentrations of total opiates in hair was observed (r = 0.346). However, when considering a single analyte, it was observed that the correlation coefficient seemed to be linked to its plasma half-life. A weak correlation coefficient corresponds to a drug with a short plasma half-life, and the correlation coefficient increases when plasma half-life increases, as r = 0.12, 0.25, and 0.64 for heroin, 6-acetylmorphine, and morphine, respectively. These results suggest that using quantitative drug measurements in hair to determine the amount of drug ingested will remain inapplicable until more is known about the factors that may influence the incorporation of drugs into hair and a way to reduce the observed variability.


Assuntos
Cabelo/química , Dependência de Heroína/reabilitação , Heroína/análise , Entorpecentes/análise , Detecção do Abuso de Substâncias/métodos , Adulto , Relação Dose-Resposta a Droga , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Cor de Cabelo , Heroína/uso terapêutico , Dependência de Heroína/metabolismo , Humanos , Masculino , Morfina/análise , Derivados da Morfina/análise , Entorpecentes/uso terapêutico
19.
Life Sci ; 63(26): PL381-4, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9877229

RESUMO

Delta9-tetrahydrocannabinol (THC) is the main psychoactive constituent of Cannabis sativa L. and its therapeutic effects are currently under intensive study. However, THC has a very low aqueous solubility (1-2 microg/mL), which restricts its use as a pharmaceutical. The present study demonstrates that THC forms a drug-cyclodextrin complex in an aqueous solution of hydroxypropyl-beta-cyclodextrin (HP-beta-CD), resulting in a thousand-fold increase in THC solubility. This improvement in solubility can be further increased by adding 0.1% hydroxypropylmethylcellulose to the HP-beta-CD solution. The present results suggest that the use of cyclodextrins might be a simple and useful method to overcome the poor water solubility of THC.


Assuntos
Ciclodextrinas/farmacologia , Dronabinol/química , Metilcelulose/análogos & derivados , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , Derivados da Hipromelose , Metilcelulose/farmacologia , Solubilidade
20.
J Anal Toxicol ; 21(5): 341-5, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9288585

RESUMO

A study was conducted to compare the performance of the OnLine and OnTrak immunoassays for benzodiazepines with gas chromatographic-mass spectrometric (GC-MS) analysis in detecting flunitrazepam (FNP) and its metabolites in human urine. Urine was collected over a 72-h period from six individuals (four male and two female) who had taken a single oral dose of either 1 or 4 mg of FNP. The OnTrak assay was run at a 100-ng/mL cutoff of nordiazepam (NDP), and the OnLine assay was run with a standard curve from zero to 200 ng/mL of NDP with and without beta-glucuronidase treatment. Each sample was analyzed by GC-MS using FNP, 7-amino-FNP, 3-hydroxy-FNP, desmethyl-FNP, 7-amino-3-hydroxy-FNP, and desmethyl-3-hydroxy-FNP as standards with beta-glucuronidase treatment. The specimens from the 1-mg dose did not yield a positive result by immunoassay over the 72-h collection period. Specimens from the 4-mg dose did yield positive results in both immunoassays. The time of the first positive result ranged from 4 to 12 h, and the time to the last positive result ranged from 18 to 60 h. Treatment of the samples with beta-glucuronidase increased the OnLine values between 20 and 60%, but it did not appreciably increase the detection time. GC-MS analysis showed no detectable levels of FNP, 3-hydroxy-FNP, desmethyl-FNP, 7-amino-3-hydroxy-FNP, and desmethyl-3-hydroxy-FNP. However, all samples collected past time zero showed detectable levels of 7-amino-FNP (> 2 ng/mL) with peak concentrations at 12-36 h. The peak levels of 7-amino-FNP by GC-MS paralleled the peak levels of the immunoassay response. The amount of 7-amino-FNP metabolite quantitated by GC-MS, however, accounted for only 15-20% of the total immunoassay crossreactive FNP metabolites.


Assuntos
Ansiolíticos/urina , Flunitrazepam/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Imunoensaio/métodos , Administração Oral , Adulto , Ansiolíticos/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Flunitrazepam/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas On-Line
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