RESUMO
3,4-methylenedioxymethamphetamine (MDMA), an illicit recreational drug, damages serotonergic nerve endings. Since the cerebrovasculature is regulated partly by the serotonergic system, MDMA may affect cerebral blood flow (CBF) in humans. We evaluated 21 abstinent recreational MDMA users and 21 age- and gender-matched healthy subjects with brain SPECT and MRI. Ten of the MDMA subjects also had repeat SPECT and MRI after receiving two doses of MDMA. Abstinent MDMA users showed no significantly different global or regional CBF (rCBF) compared to the control subjects. However, within 3 weeks after MDMA administration, rCBF remained decreased in the visual cortex, the caudate, the superior parietal and dorsolateral frontal regions compared to baseline rCBF. The decreased rCBF tended to be more pronounced in subjects who received the higher dosage of MDMA. Two subjects who were scanned at 2-3 months after MDMA administration showed increased rather than decreased rCBF. Low-dose recreational MDMA use does not cause detectable persistent rCBF changes in humans. The lack of long-term rCBF changes may be due to a non-significant effect of serotonergic deficits on rCBF, or regeneration of serotonergic nerve terminals. The subacute decrease in rCBF after MDMA administration may be due to the direct effect of MDMA on the serotonergic system or the indirect effects of its metabolites on the dopaminergic system; the preliminary data suggest these effects may be transient.
Assuntos
Encéfalo/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Imageamento por Ressonância Magnética , N-Metil-3,4-Metilenodioxianfetamina/efeitos adversos , Serotoninérgicos/efeitos adversos , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , N-Metil-3,4-Metilenodioxianfetamina/administração & dosagem , Compostos Radiofarmacêuticos , Serotoninérgicos/administração & dosagem , Tecnécio Tc 99m Exametazima , Fatores de TempoRESUMO
3,4-methylenedioxymethamphetamine (MDMA) is an illicit drug that has been associated with serotonergic axonal degeneration in animals. This study evaluates neurochemical abnormalities in recreational MDMA users. Twenty-two MDMA users and 37 normal subjects were evaluated with magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy ((1)H MRS) in the mid-frontal, mid-occipital, and parietal brain regions. (1)H MRS showed normal N-acetyl (NA) compounds in all brain regions. The myo-inositol (MI) concentration (+16.3%, P = 0.04) and the MI to creatine (CR) ratio (+14.1%, P = 0. 01) were increased in the parietal white matter of MDMA users. The cumulative lifetime MDMA dose showed significant effects on [MI] in the parietal white matter and the occipital cortex. The normal NA concentration suggests a lack of significant neuronal injury in recreational MDMA users. However, the usage-related increase in MI suggests that exposure to MDMA, even at recreational doses, may cause increased glial content. J. Magn. Reson. Imaging 1999;10:521-526.
Assuntos
Química Encefálica , Encéfalo/efeitos dos fármacos , Alucinógenos/efeitos adversos , Espectroscopia de Ressonância Magnética , N-Metil-3,4-Metilenodioxianfetamina/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análise , Encéfalo/patologia , Colina/análise , Creatina/análise , Feminino , Humanos , Inositol/análise , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Substâncias/patologiaRESUMO
N,N-Dimethyltryptamine (DMT), harmine, harmaline and tetrahydroharmine (THH) are the characteristic alkaloids found in Amazonian sacraments known as hoasca, ayahuasca, and yajè. Such beverages are characterized by the presence of these three harmala alkaloids, where harmine and harmaline reversibly inhibit monoamine oxidase A (MAO-A) while tetrahydroharmine weakly inhibits the uptake of serotonin. Together, both actions increase central and peripheral serotonergic activity while facilitating the psychoactivity of DMT. Though the use of such 'teas' has be known to western science for over 100 years, little is known of their pharmacokinetics. In this study, hoasca was prepared and administered in a ceremonial context. All four alkaloids were measured in the tea and in the plasma of 15 volunteers, subsequent to the ingestion of 2 ml hoasca/kg body weight, using gas (GC) and high pressure liquid chromatographic (HPLC) methods. Pharmacokinetic parameters were calculated and peak times of psychoactivity coincided with high alkaloid concentrations, particularly DMT which had an average Tmax of 107.5 +/- 32.5 min. While DMT parameters correlated with those of harmine, THH showed a pharmacokinetic profile relatively independent of harmine's.
Assuntos
Alcaloides/farmacocinética , Alucinógenos/farmacocinética , Adulto , Alcaloides/sangue , Alcaloides/farmacologia , Área Sob a Curva , Meia-Vida , Alucinógenos/sangue , Alucinógenos/farmacologia , Humanos , Masculino , Valores de ReferênciaRESUMO
The Amazonian psychoactive plant beverage ayahuasca has attracted increasing interest in recent years. Little attention has been given, however, to potentially dangerous interactions with other drugs. In particular, the interaction between the potent monoamine oxidase-inhibiting harmala alkaloids in ayahuasca and the selective serotonin reuptake inhibitor (SSRI) class of antidepressants may induce a serotonin syndrome with potentially grave outcome. Caution is advised when combining ayahuasca with certain pharmaceutical drugs.
Assuntos
Plantas Medicinais/efeitos adversos , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Síndrome da Serotonina/induzido quimicamente , Adulto , Brasil , Interações Medicamentosas , Fluoxetina/efeitos adversos , Interações Ervas-Drogas , Humanos , Masculino , Plantas Medicinais/química , Síndrome da Serotonina/psicologiaRESUMO
The present study examined the persistent functional consequences associated with exposure to single and multiple doses of (+/-) 3,4-methylenedioxymethamphetamine (MDMA) as reflected by the neuroendocrine responses to d,l-fenfluramine (FEN). Adult male rats were administered a single dose of MDMA (20 mg/kg, s.c.) and challenged 2 weeks later with saline or FEN (2, 4, 6 and 8 mg/kg, s.c.). The corticotropin (ACTH) response to FEN (6 and 8 mg/kg) was blunted and the prolactin response to FEN (4 and 6 mg/kg) was enhanced in MDMA pre-treated rats. The ACTH and prolactin responses to FEN (6 mg/kg, s.c.) were then evaluated 4, 8 and 12 months after exposure to single and multiple doses MDMA (20 mg/kg, s.c. and 20 mg/kg, s.c., bid, x 4 days, respectively). The ACTH response to FEN was significantly reduced at 4 and 8 months in both MDMA treatment groups, and at 12 months in the multiple dose group only. In contrast, the prolactin response to FEN was enhanced in both groups of MDMA treated rats at 4 months, but only in the multiple dose group at 8 months. By 12 months, the prolactin response to FEN had normalized. Following multiple doses of MDMA, 5-HT concentrations were reduced significantly in the frontal cortex at 4 and 12 months. The results indicate that exposure to single or multiple doses of MDMA can produce functional alterations which can persist for months, whereas the biochemical sequelae were less robust and shorter lived.
Assuntos
Hormônio Adrenocorticotrópico/sangue , Fenfluramina/farmacologia , Alucinógenos/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Prolactina/sangue , Serotoninérgicos/farmacologia , Serotonina/sangue , Hormônio Adrenocorticotrópico/metabolismo , Animais , Córtex Cerebral/efeitos dos fármacos , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Masculino , Prolactina/metabolismo , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismoRESUMO
Harmine, harmaline, tetrahydroharmine (THH), and N,N-dimethyltryptamine (DMT) were quantitated in plasma from 15 healthy male volunteers after the ingestion of ayahuasca, a beverage that has been used for religious purposes in Brazil since pre-Columbian times. A growing awareness of the interest in this ancient shamanistic practice in modern urban cultures and the widespread popular dissemination of the inebriant effects and type and sources of the plant admixtures used to prepare the beverage have provided additional impetus for this study. The three harmala alkaloids were quantitated from protein-precipitated plasma by high-performance liquid chromatography using fluorescence detection. Recovery from blank human plasma was quantitative, and the limit of quantitation (LOQ) was below 2 ng/mL of plasma for each of the harmala alkaloids. Standard concentrations ranged from 10 to 250 ng/mL for harmine and THH and from 1.0 to 25.0 ng/mL for harmaline, respectively. Linearity was observed for harmine, harmaline, and THH within these respective ranges. The highest concentrations of harmala alkaloids in human plasma were found to be 222.3 ng/mL for harmine, 134.5 ng/mL for THH, and 9.4 ng/mL for harmaline. DMT was quantitated by gas chromatography using nitrogen-phosphorus detection after liquid-liquid extraction with diphenhydramine as an internal standard. DMT recovery was quantitative, and the limit of detection and LOQ were 0.5 and 5 ng/mL, respectively. Linearity for DMT was observed from 5 to 1000 ng/mL. The one-step extraction method for DMT and the protein precipitation method for the three harmala alkaloids afford rapid, sensitive, and quantitative analyses of these alkaloids with minimal analyte loss. The analytical methods also may be applicable to other matrices, including whole blood and urine samples and homogenized tissue specimens. These are the first reported observations of DMT and harmala alkaloids in plasma after ritual ingestion of ayahuasca.
Assuntos
Bebidas , Harmalina/sangue , Harmina/análogos & derivados , N,N-Dimetiltriptamina/sangue , Administração Oral , Brasil , Calibragem , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Difenidramina/sangue , Harmina/sangue , Humanos , Masculino , Nitrogênio/química , Fósforo/química , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
A multinational, collaborative, biomedical investigation of the effects of hoasca (ayahuasca), a potent concoction of plant hallucinogens, was conducted in the Brazilian Amazon during the summer of 1993. This report describes the psychological assessment of 15 long-term members of a syncretic church that utilizes hoasca as a legal, psychoactive sacrament as well as 15 matched controls with no prior history of hoasca ingestion. Measures administered to both groups included structured psychiatric diagnostic interviews, personality testing, and neuropsychological evaluation. Phenomenological assessment of the altered state experience as well as semistructured and open-ended life story interviews were conducted with the long-term use hoasca group, but not the hoasca-naive control group. Salient findings included the remission of psychopathology following the initiation of hoasca use along with no evidence of personality or cognitive deterioration. Overall assessment revealed high functional status. Implications of this unusual phenomenon and need for further investigation are discussed.
Assuntos
Alucinógenos/farmacologia , Plantas Medicinais , Religião e Medicina , Adulto , Brasil/epidemiologia , Cognição/efeitos dos fármacos , Harmina/farmacologia , Humanos , Magia , Masculino , Medicina Tradicional , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Personalidade/efeitos dos fármacos , Escalas de Graduação Psiquiátrica , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/psicologia , Chá , Aprendizagem Verbal/efeitos dos fármacosRESUMO
3,4-Methylenedioxymethamphetamine (MDMA) is a phenethylamine with potent effects on serotonergic neurotransmission which has been the object of controversy over its potential as a therapeutic adjunct versus its possible risks for causing neurotoxic injury. This paper discusses the background, methodology and preliminary findings of the first FDA approved Phase I study prospectively evaluating the effects of MDMA administration in humans. Six subjects with prior experience with MDMA were administered two different dosages of MDMA and an inactive placebo utilizing a randomized, double-blind methodologic design. Dosages from 0.25 to 1.0 mg/kg, p.o., were administered. All subjects tolerated the procedures without any overt evidence of physical discomfort or psychological distress. MDMA produced a modest increase in heart rate and blood pressure. The threshold dose for the stimulation of ACTH and prolactin appeared to be between 0.5 and 0.75 mg/kg, with the two higher doses clearly stimulating both ACTH and prolactin. Methodology for assessing MDMA's effects on serotonergic neurotransmission is discussed.
Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Alucinógenos/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Serotonina/fisiologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Circulação Cerebrovascular , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hormônios/sangue , Humanos , Masculino , Estudos Prospectivos , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
The binding of [3H]citalopram to the platelet 5-hydroxytryptamine (5-HT) transporter was measured in a group of healthy male drinkers of ayahuasca, a psychoactive sacrament indigenous to Amazonia, and a group healthy male controls. An increased number of binding sites (Bmax) in the platelets of ayahuasca drinkers was found, while the dissociation constant (Kd) remained the same for both groups. If indicative of neuronal 5-HT uptake activity, these results would suggest a decreased concentration of extracellular 5-HT, or a response to increased production and release of 5-HT. Such changes in 5-HT synaptic activity, in this case, should not be misinterpreted as an indication of developing neurological or psychiatric illness.
Assuntos
Plaquetas/metabolismo , Alucinógenos/farmacologia , Plantas Tóxicas/química , Receptores de Serotonina/metabolismo , Adulto , Brasil , Citalopram , Cultura , Humanos , Masculino , Pessoa de Meia-Idade , Receptores de Serotonina/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosRESUMO
3,4-Methylenedioxymethamphetamine (MDMA) has been at the center of a debate over its potential benefits as an adjunct to psychotherapy versus its capability for neurotoxic effects and is currently classified as a Schedule 1 drug by the Drug Enforcement Administration (DEA). However, as yet, there is very little methodological data on the subjective experience of the MDMA-induced state or its psychological and behavioral sequelae. The present study was, therefore, designed to obtain this kind of information. Twenty psychiatrists who had taken MDMA previously were evaluated using a semistructured interview. Subjective experience of the actual MDMA-induced state, as well as both short-term (less than 1 week) and relatively longer term (greater than 1 week) sequelae, were examined retrospectively. Side effects, insight gained, pleasure, and intensity of the MDMA experience were evaluated as were the influence of set and setting at the time the MDMA was taken and the dosage utilized. Finally, the authors discuss methodological problems and limitations of a study of this type.
Assuntos
3,4-Metilenodioxianfetamina/análogos & derivados , Drogas Desenhadas/farmacologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , 3,4-Metilenodioxianfetamina/efeitos adversos , 3,4-Metilenodioxianfetamina/farmacologia , 3,4-Metilenodioxianfetamina/uso terapêutico , Adulto , Terapia Combinada , Drogas Desenhadas/efeitos adversos , Drogas Desenhadas/uso terapêutico , Emoções/efeitos dos fármacos , Feminino , Humanos , Relações Interpessoais , Masculino , Transtornos Mentais/induzido quimicamente , Transtornos Mentais/tratamento farmacológico , Pessoa de Meia-Idade , N-Metil-3,4-Metilenodioxianfetamina , Sistema Nervoso/efeitos dos fármacos , Percepção/efeitos dos fármacos , Psicoterapia , Projetos de Pesquisa/normasAssuntos
3,4-Metilenodioxianfetamina/análogos & derivados , Drogas Desenhadas/efeitos adversos , Sistema Nervoso/efeitos dos fármacos , 3,4-Metilenodioxianfetamina/efeitos adversos , 3,4-Metilenodioxianfetamina/uso terapêutico , Animais , Terapia Combinada , Drogas Desenhadas/uso terapêutico , Humanos , Transtornos Mentais/terapia , N-Metil-3,4-Metilenodioxianfetamina , Doenças do Sistema Nervoso/induzido quimicamente , Psicoterapia , Projetos de Pesquisa/normas , Serotonina/fisiologia , Transtornos Relacionados ao Uso de Substâncias/etiologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Transmissão Sináptica/efeitos dos fármacosRESUMO
Two cases are presented which illustrate the dangers inherent in utilizing a polypharmacy approach in treating children with psychotropic medication. In each case, severe adverse effects, including cognitive and mood deterioration, were experienced by the child when treated with a combination of methylphenidate and imipramine. Possible mechanisms at the neurotransmitter level are described as postulated determinants for this pharmacological interaction.
Assuntos
Imipramina/efeitos adversos , Metilfenidato/efeitos adversos , Adolescente , Agressão/efeitos dos fármacos , Criança , Interações Medicamentosas , Humanos , Masculino , Receptores Colinérgicos/efeitos dos fármacos , Receptores de Neurotransmissores/efeitos dos fármacosRESUMO
Although genital exhibitionism has traditionally been almost exclusively associated with males, similar behavior may occur in certain women with a particular set of life circumstances and precipitants. A case report is presented of a woman whose emotional deprivation led to feelings of rejection and the inability to develop empathic relationships. Her self-esteem relied on success in her profession, and when she lost her position, she sought validation through exhibitionism. Despite the widely held view that genital exhibitionism producing arousal and stimulation in the subject occurs only in men, this case demonstrates that such phenomena may exist in women as well.