RESUMO
The hippocampal formation has been shown to be particularly vulnerable to the neurotoxic effects of chronic ethanol consumption. It was hypothesized that this damage was due to the disruption of the expression of neurotrophic factors and certain other proteins within the hippocampus. By using real-time reverse transcription-polymerase chain reaction (RT-PCR) techniques, this study aimed to determine whether chronic ethanol consumption could alter the mRNA expression level of brain-derived neurotrophic factor (BDNF), glial-derived neurotrophic factor (GDNF), and oligodendrocyte myelin glycoprotein (OMgp) in the hippocampus. Wistar male rats received an unrestricted access to a liquid diet containing 5% (v/v) ethanol as the sole source of fluid from 10 to 29 weeks of age. Control rats had unlimited access to a liquid diet containing an isocaloric amount of sucrose. We found that chronic ethanol consumption did not cause significant changes in the levels of mRNA for BDNF and GDNF. However, OMgp mRNA showed a significant deficit in ethanol-treated animals. It is suggested that this deficit may be related to the demyelination that is commonly observed in human alcoholics and that this may contribute to the functional and cognitive deficits.
Assuntos
Transtornos do Sistema Nervoso Induzidos por Álcool/metabolismo , Doenças Desmielinizantes/induzido quimicamente , Etanol/farmacologia , Hipocampo/efeitos dos fármacos , Glicoproteína Associada a Mielina/genética , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Transtornos do Sistema Nervoso Induzidos por Álcool/induzido quimicamente , Transtornos do Sistema Nervoso Induzidos por Álcool/fisiopatologia , Animais , Atrofia/induzido quimicamente , Atrofia/metabolismo , Atrofia/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/genética , Depressores do Sistema Nervoso Central/farmacologia , Doença Crônica , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/fisiopatologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Proteínas Ligadas por GPI , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Proteínas da Mielina , Glicoproteína Mielina-Oligodendrócito , Fibras Nervosas Mielinizadas/metabolismo , Fibras Nervosas Mielinizadas/patologia , Tamanho do Órgão/efeitos dos fármacos , Tamanho do Órgão/fisiologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos WistarRESUMO
Chronic ethanol consumption has adverse effects on the central nervous system. Hippocampus is one of the target sites of ethanol neurotoxicity. Hippocampal damage is known to result in impairment of learning and memory. This study was aimed to determine whether chronic ethanol consumption could alter the expression levels of brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF) mRNAs in the hippocampus. Male Wistar rats were given unrestricted access to a liquid diet containing 5% (v/v) ethanol as the sole fluid source for 19 weeks beginning at 10 weeks of age. The expression levels of BDNF and GDNF mRNAs in the hippocampus were analyzed by real-time reverse transcription-polymerase chain reaction (RT-PCR) analysis. The present study revealed that chronic ethanol consumption did not result in significant changes in the expression levels of BDNF and GDNF mRNAs. Our present results showed no significant alteration in the expression of these neurotrophic factors; these results will lead to further studies to examine the possible alterations in the gene expression of various neurotrophins that are related to hippocampal functions including learning and memory.
Assuntos
Transtornos Relacionados ao Uso de Álcool/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressores do Sistema Nervoso Central/toxicidade , Etanol/toxicidade , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Hipocampo/efeitos dos fármacos , Transtornos Relacionados ao Uso de Álcool/patologia , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Dieta , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The effects of maternal deprivation (MD) during early postnatal life on the brain-derived neurotrophic factor (BDNF) level were investigated in the present study. Wistar rats were assigned to either maternal deprivation or mother-reared control (MRC) groups. MD manipulation was achieved by separating rat pups from their mothers for 3h a day during postnatal days (PND) 10-15. At 16, 20, 30, and 60 days of age, the level of BDNF mRNA in the hippocampal formation of each group was determined using real-time PCR analysis. Early postnatal maternal deprivation of rat pups resulted in a significant increase in body weight at 60 days of age. The expression of BDNF mRNA in the hippocampus was significantly decreased at 16 days of age, and increased at 30 and 60 days of age. These data indicate that even a brief period of maternal deprivation during early postnatal life can affect hippocampal BDNF expression.
