SEARCH FOR MORPHINE-ANTAGONISTIC AGENTS IN HUMAN CSF AND BRAIN

A chromatographic fraction with morphine-antagonistic properties, here called A-FACTOR, was purified from human cerebrospinal fluid (CSF) and brain. It was tested for activity on the electrically stimulated myenteric plexus-longitudinal muscle preparation of the guinea-pig ileum. The factor not only counteracted normorphine suppression of the twitch, but actually potentiated it in its absence. Levels in the CSF appeared to be higher after opiate treatment. The activity showed an unequal distribution in brain with highest concentrations in opiate receptor-rich areas.