RESUMO
Morphine and beta-endorphin inhibit the shaking response of pentobarbital-anesthetized rats to ice water. Stereotaxically guided administration of antibodies to cerebroside sulfate into the periaqueductal gray region, the most sensitive brain region in which to demonstrate inhibition of this response, antagonizes the effect of morphine and beta-endorphin. These results suggest that cerebroside sulfate may be an integral component of an opiate receptor in rat brain.
Assuntos
Encéfalo/imunologia , Endorfinas/antagonistas & inibidores , Morfina/antagonistas & inibidores , Receptores Opioides/imunologia , Sulfoglicoesfingolipídeos/imunologia , Animais , Reações Antígeno-Anticorpo , Comportamento Animal/efeitos dos fármacos , Bioensaio , Aqueduto do Mesencéfalo , Masculino , Pentobarbital/farmacologia , RatosRESUMO
Sulfogalactosylceramide (or sulfatide) has been localized in the central nervous system by indirect immunofluorescence. This glycosphingolipid belongs essentially to the myelinated areas. Nevertheless, it has also been found in ependymal cells, subpial processes and, in the cerebellum, in the Bergmann fibers. In the brain areas, known to be enriched in opiate receptors, some cells and nerve terminals are also sulfatide positive. In this latter localization, opiates were shown to selectively inhibit binding of the antisulfatide antibodies. We have also shown that antisulfatide inhibited, in vitro, the stereo-specific binding of narcotic drugs and that they antagonized the in vivo effects of morphine and beta-endorphin.