RESUMO
In this study we investigated the expression of brain-derived neurotrophic factor (BDNF) and c-fos mRNA in the hippocampal formation after febrile seizures (FSs) with in situ hybridization histochemistry using riboprobes. The induction of BDNF mRNA was firstly observed in the dentate gyrus at 30 min after FSs. The expression in the dentate gyrus peaked at 3 h and returned to basal level at 24 h. It was also observed in the CA3 of hippocampus from 2 to 3 h. The induction of c-fos mRNA was observed in the dentate gyrus at 30 min and 1 h. These observations suggest that BDNF and c-fos are the genes whose expression can be altered by FSs and might be related to pathologic alterations after FSs.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Regulação da Expressão Gênica/fisiologia , Hipocampo/metabolismo , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , RNA Mensageiro/metabolismo , Convulsões Febris/metabolismo , Animais , Giro Denteado/metabolismo , Giro Denteado/fisiopatologia , Hipocampo/fisiopatologia , Hipertermia Induzida , Masculino , Plasticidade Neuronal/genética , Ratos , Ratos Sprague-Dawley , Convulsões Febris/genética , Convulsões Febris/fisiopatologia , Regulação para Cima/genéticaRESUMO
Protein tyrosine phosphorylation is regulated by protein tyrosine kinase and protein tyrosine phosphatase activities. These two counteracting proteins are implicated in cell growth and transformation. Using polymerase chain reaction with degenerate primers, we have identified a novel mouse protein tyrosine phosphatase (PTP). This cDNA contains a single open reading frame of the predicted 926 amino acids. Those predicted amino acids showed significant identity with human megakaryocyte protein-tyrosine phosphatase by 91% in nucleotide sequences and 94% in amino acid sequences. We have identified that expression of this PTP is highly enriched in the testis in mouse and human and has been termed here as a 'testis-enriched phosphatase' (TEP). Northern analysis detected two mRNA species of 3.7 and 3.2kb for this PTP in mouse testis and the expression of TEP is regulated during development. The recombinant phosphatase domain possesses protein tyrosine phosphatase activity when expressed in Escherichia coli. Immunohistochemical analysis of the cellular localization of TEP on mouse testis sections showed that this PTP is specifically expressed in spermatocytes and spermatids within seminiferous tubules, suggesting an important role in spermatogenesis.