RESUMO
The major stages of oligodendrocyte differentiation are defined by the presence or absence of certain myelin-specific proteins. Events leading to the successful processing of these proteins, such as the folding, assembly, and trafficking of these proteins through the biosynthetic pathway, are largely undefined. In the present study, we have examined both cultured primary oligodendrocytes and immortalized oligodendrocyte cell lines for the presence of molecular chaperones and/or vesicle transport proteins. We find that a select set of these proteins are expressed relatively early in oligodendrocyte differentiation, whereas a characteristically different set of proteins are expressed at later stages of oligodendrocyte differentiation. In other systems, these proteins participate in the folding and assembly of protein complexes, in the prevention of protein aggregation, as well as the trafficking of proteins via vesicles to specific subcellular destinations including the plasma membrane. Some of the chaperones and/or vesicle transport proteins investigated in this study may play a pivotal role in the certain aspect of myelin biogenesis.
Assuntos
Encéfalo/fisiologia , Proteínas de Membrana/biossíntese , Chaperonas Moleculares/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Oligodendroglia/citologia , Oligodendroglia/fisiologia , Animais , Animais Recém-Nascidos , Encéfalo/citologia , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Imuno-Histoquímica , RatosRESUMO
Naltrexone significantly attenuated self-injurious behavior in a 20-year-old mildly retarded autistic male patient. The patient was videotaped daily and behavior was evaluated with a time-sampling procedure. Behavioral ratings of SIB frequency, SIB severity, and activity were collected automatically with a computerized system. Learning and memory were tested on a weekly basis with a modification of a paired associate learning test (PALT). Treatment with naltrexone resulted in (a) attenuation of SIB in the unstructured setting and (b) improvements in learning and memory without influencing activity levels.