Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 2 de 2
Filtrar
Mais filtros

Medicinas Complementares
Base de dados
Ano de publicação
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Mol Neurosci ; 30(3): 341-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17401159

RESUMO

A low abuse liability is reported for tramadol, an analgesic drug centrally acting through either opioid or nonopioid mechanisms. In this paper, we evaluated the effects of the repeated administration (7 d) of different doses of tramadol (10, 20, and 80 mg/kg, intraperitoneally) on the opioid precursor prodynorphin biosynthesis, in comparison with morphine (10 mg/kg, intraperitoneally), in the rat central nervous system (CNS). Northern analysis showed that morphine and tramadol produced different effects. While morphine caused a downregulation of prodynorphin mRNA levels in all investigated areas (hypothalamus, hippocampus, and striatum), tramadol did not cause any significant change in the striatum, and did not decrease prodynorphin biosynthesis in the hypothalamus and in the hippocampus, at nontoxic doses (10 and 20 mg/kg). The highest dose of tramadol (80 mg/kg) decreased prodynorphin mRNA levels in the hypothalamus and the hippocampus but not in the striatum. These data give some information on tramadol effects at molecular level in the CNS. They indicate that the alterations of prodynorphin gene expression caused by tramadol and morphine show a different pattern that may be related to the different abuse potential of the two analgesic drugs.


Assuntos
Encéfalo/fisiologia , Encefalinas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Precursores de Proteínas/genética , Tramadol/farmacologia , Analgésicos Opioides/farmacologia , Animais , Northern Blotting , Encéfalo/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/fisiologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Hipotálamo/efeitos dos fármacos , Hipotálamo/fisiologia , Injeções Intraperitoneais , Masculino , Morfina/farmacologia , RNA/genética , RNA/isolamento & purificação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Tramadol/administração & dosagem
2.
J Neurochem ; 91(1): 30-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15379884

RESUMO

The neuropeptide nociceptin/orphanin FQ (N/OFQ) has been suggested to play a facilitatory role in kainate seizure expression. Furthermore, mRNA levels for the N/OFQ precursor are increased following kainate seizures, while its receptor (NOP) density is decreased. These data suggest increased N/OFQ release. To obtain direct evidence that this is the case, we have developed a microdialysis technique, coupled with a sensitive radioimmunoassay, that allows measurement of N/OFQ release from the hippocampus and thalamus of awake, freely moving animals. In both these brain areas, the spontaneous N/OFQ efflux decreased by approximately 50% and 65% when Ca2+ was omitted and when tetrodotoxin was added to the perfusion medium, respectively. Perfusion of the dialysis probe with high K+ increased N/OFQ release (approximately threefold) in a Ca2+-dependent and tetrodotoxin-sensitive manner. Kainate seizures caused a twofold increase in N/OFQ release followed, within 3 h, by a return to baseline levels. Approximately 5 h after kainate, a late increase in N/OFQ release was observed. On the following day, when animals were having only low grade seizures, N/OFQ release was not significantly different from normal. These phenomena were observed with similar patterns in the hippocampus and in the thalamus. The present data indicate that acute limbic seizures are associated with increased N/OFQ release, which may prime the molecular changes described above, i.e. cause down-regulation of NOP receptors and activation of N/OFQ biosynthesis.


Assuntos
Hipocampo/metabolismo , Microdiálise/métodos , Peptídeos Opioides/metabolismo , Convulsões/metabolismo , Tálamo/metabolismo , Animais , Química Encefálica , Eletroencefalografia/métodos , Hipocampo/efeitos dos fármacos , Ácido Caínico , Masculino , Potássio/farmacologia , Radioimunoensaio/métodos , Ratos , Ratos Sprague-Dawley , Convulsões/induzido quimicamente , Convulsões/fisiopatologia , Estatísticas não Paramétricas , Tálamo/efeitos dos fármacos , Fatores de Tempo , Nociceptina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA