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1.
Scand J Clin Lab Invest ; 65(3): 189-99, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16095048

RESUMO

Bufotenine and N,N-dimethyltryptamine (DMT) are hallucinogenic dimethylated indolethylamines (DMIAs) formed from serotonin and tryptamine by the enzyme indolethylamine N-methyltransferase (INMT) ubiquitously present in non-neural tissues. In mammals, endogenous bufotenine and DMT have been identified only in human urine. The DMIAs bind effectively to 5HT receptors and their administration causes a variety of autonomic effects, which may reflect their actual physiological function. Endogenous levels of bufotenine and DMT in blood and a number of animal and human tissues were determined using highly sensitive and specific quantitative mass spectrometric techniques. A new finding was the detection of large amounts of bufotenine in stools, which may be an indication of its role in intestinal function. It is suggested that fecal and urinary bufotenine originate from epithelial cells of the intestine and the kidney, respectively, although the possibility of their synthesis by intestinal bacteria cannot be excluded. Only small amounts of the DMIAs were found in somatic or neural tissues and none in blood. This can be explained by rapid catabolism of the DMIAs by mitochondrial monoamino-oxidase or by the fact that the dimethylated products of serotonin and tryptamine are not formed in significant amounts in most mammalian tissues despite the widespread presence of INMT in tissues.


Assuntos
Bufotenina/sangue , Bufotenina/farmacocinética , Alucinógenos/sangue , Alucinógenos/farmacocinética , N,N-Dimetiltriptamina/sangue , N,N-Dimetiltriptamina/farmacocinética , Receptores de Serotonina/metabolismo , Animais , Bufotenina/metabolismo , Bufotenina/urina , Cromatografia Líquida de Alta Pressão , Fezes/química , Alucinógenos/metabolismo , Alucinógenos/urina , Humanos , Ligantes , Estrutura Molecular , N,N-Dimetiltriptamina/química , N,N-Dimetiltriptamina/urina , Coelhos , Ratos , Sensibilidade e Especificidade
2.
Scand J Clin Lab Invest ; 61(7): 547-56, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11763413

RESUMO

A new method for the determination of N,N-dimethyl-5-hydroxytryptamine (bufotenine), N,N-dimethyltryptamine (DMT)*, 5-methoxy-N,N-dimethyltryptamine (5-MeODMT), and N-methyltryptamine (NMT) was developed using high-performance liquid chromatography-mass spectrometry (HPLC-MS). Identification of the analytes is based on liquid chromatographic retention times of analytes and two fragment ions produced by a triple quadrupole mass spectrometer. Quantification is based on electrospray ionization (ESI), and multiple reaction monitoring (MRM) was also utilized for getting better selectivity. The analytes and internal standard were separated from the urine matrix by solid-phase extraction (SPE). The method was applied for the determination of these compounds in urine samples of patients from surgical, medical and psychiatric wards. Of the dimethylated amines, only bufotenine was found in significant amounts (up to 34 microg/L). In keeping with our earlier results, the bufotenine excretion of psychiatric patients was found to be higher than that of the somatic patients. Method, procedure, considerations, statistical evaluations and urine sample spectra are presented.


Assuntos
Bufotenina/urina , Cromatografia Líquida de Alta Pressão/métodos , Alucinógenos/urina , Metoxidimetiltriptaminas/urina , N,N-Dimetiltriptamina/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Triptaminas/urina , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Scand J Clin Lab Invest ; 60(8): 695-701, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11218152

RESUMO

Increased intestinal permeability has been proposed as one aetiological factor for inflammatory bowel diseases (IBD). We have previously found that intestinal permeability of a water-soluble contrast medium, iohexol, correlates with disease activity. The objective was to compare the iohexol test with the lactulose-mannitol ratio, which is a more extensively studied permeability marker, in patients with active IBD. Urinary excretion of iohexol was compared to the lactulose-mannitol ratio in 22 patients with an exacerbation of IBD and in 10 healthy controls. Median intestinal absorption of iohexol was 0.64% (range 0.13-3.8%) in the 22 patients and 0.3% (range 0.15-0.54%) in the controls (p = 0.016), whereas the median lactulose-mannitol ratio was 0.037 (range 0.01-0.260) in patients and 0.03 (range 0.004-0.063) in controls (N.S.). Correlation between urinary excretion of iohexol and lactulose-mannitol ratio was positive (R = +0.41, p = 0.018). The urinary excretion of iohexol correlated positively with endoscopic disease activity (R = +0.74, p < 0.001) and the modified Harvey-Bradshaw index (R = +0.44, p = 0.04). The lactulose-mannitol ratio correlated positively with endoscopic disease activity (R = +0.44, p = 0.05), but correlations with clinical index or c-reactive protein were poor. In conclusion, the iohexol test is a superior activity marker compared to the lactulose-mannitol ratio which probably reflects, instead, some pathogenic property of IBD.


Assuntos
Doenças Inflamatórias Intestinais/fisiopatologia , Absorção Intestinal , Iohexol , Lactulose , Manitol , Adulto , Idoso , Colite Ulcerativa/fisiopatologia , Doença de Crohn/fisiopatologia , Endoscopia Gastrointestinal , Feminino , Humanos , Iohexol/metabolismo , Lactulose/urina , Masculino , Manitol/urina , Pessoa de Meia-Idade , Permeabilidade , Soluções
4.
Forensic Sci Int ; 77(3): 191-210, 1996 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-8819994

RESUMO

A comprehensive drug screening procedure for detecting drugs in the blood samples of car drivers suspected of driving under the influence of drugs, is presented. Amphetamines, cannabinoids, opioids, cocaine and benzodiazepines were screened by an immunological EMIT ETS system after acetone precipitation. Gas chromatographic methods were used to screen and quantitate basic, neutral and acidic drugs. The free amino groups of basic drugs were derivatized with heptafluorobutyric anhydride. Analysis was performed by a dual channel gas chromatograph combined with a nitrogen phosphorus and an electron capture detector. Phenyltrimethylammonium hydroxide was used as a methylathing agent for acidic substances before analysis with a gas chromatograph connected to a nitrogen phosphorus detector. A gas chromatograph/mass spectrometry was used as a common confirmation method. Tetrahydrocannabinol was quantitated after bis(trimethylsilyl)trifluoroacetamide derivatization, opiates after pentafluoropropionic anhydride derivatization and benzoylecgonine after pentafluoropropionic anhydride and pentafluoropropanol derivatization. Excluding benzodiazepines, which were confirmed with a gas chromatograph connected to a nitrogen phosphorus and an electron capture detector, the other basic drugs as well as the acidic drugs were confirmed after the same derivatization procedures as in the screening methods. Alcohols were quantitated in triplicate by gas chromatography using three different kinds of columns. Although urine is the most important specimen for screening abused drugs, it has only limited use in forensic toxicology. The described system is most useful for analyzing a wide range of substances, including illicit drugs, benzodiazepines, barbiturates, antidepressants and phenothiazenes in forensic samples when urine is not available.


Assuntos
Acidentes de Trânsito/prevenção & controle , Condução de Veículo , Programas de Rastreamento/métodos , Transtornos Relacionados ao Uso de Substâncias/sangue , Cromatografia Gasosa , Técnica de Imunoensaio Enzimático de Multiplicação , Humanos
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