Preparation of enriched fractions from cerebral cortex containing isolated, metabolically active neuronal and glial cells.

摘要: 1. A procedure has been developed for the separation of intact metabolically active neuronal and glial cells in bulk from rat cerebral cortex. Separation depended on dispersion tissue a Ficoll medium followed by centrifugation discontinuous gradient. Up to 1.5x10(7) could be collected 12 brains within 3hr. The morphological appearance these seemed good, fraction was 8.5-fold purified terms dry weight. Average weight per neuron 2300mumug. Maximum contamination 11% as determined carbonic anhydrase measurements. free neurons but contained various subcellular contaminants. 2. Concentrations nucleic acids, phospholipid, protein phosphoprotein were separated fractions. richer than all except phospholipid. Succinate dehydrogenase equally distributed between glia 1.8-fold enriched cytochrome oxidase. 3. Measurement respiration showed an endogenous uptake 117mmumoles oxygen/mg./hr. neurons, 173mmumoles glia. Addition substrate at 10mm stimulated similar values both With glucose it 390, with pyruvate 355, glutamate 215mmumoles This represented larger stimulation compared basal level. 4. Respiration cell suspensions 70-80% that slices, whereas fractionated homogenates had respiratory rates only one-third those suspensions. Lactate content maintained during gradient washing. 5. possible uses isolated preparations are discussed.