Extracellular release of cerebral macromolecules during potassium- and low-calcium-induced seizures.
Cerebral cortex of cat was incubated with 14C-lysine and 3H-glucosamine. Subsequent superfusion of the surface of the cortex resulted in the release into the superfusate of a variety of 14C- and 3H-labeled compounds including proteins, glycoproteins, and gangliosides. The release of 14C- and 3H-labeled macromolecules could be considerably enhanced by topical addition of 40 mM K+, WHICH INDUCED Epileptiform EEG activity. Peaks in efflux could also be correlated with the onset of seizures induced by superfusion with low (0.75 mM) Ca2+ media. Control experiments in which the cortex was prelabeled with 14C-carboxyl-inulin and 3H2O indicate that the release of macromolecules was not a direct consequence of the altered blood flow that may occur during convulsions.
D000818:Animals; D002250:Carbon Radioisotopes; D002415:Cats; D002540:Cerebral Cortex / Q000378:metabolism*; D005944:Glucosamine / Q000378:metabolism*; D006996:Hypocalcemia / Q000378:metabolism*; D007444:Inulin / Q000378:metabolism; D008239:Lysine / Q000378:metabolism*; D046911:Macromolecular Substances; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D011189:Potassium Chloride; D012640:Seizures / Q000139:chemically induced / Q000209:etiology / Q000378:metabolism*; D014316:Tritium; D014867:Water / Q000378:metabolism
D002250:Carbon Radioisotopes; D046911:Macromolecular Substances; D009419:Nerve Tissue Proteins; D014867:Water; D014316:Tritium; D011189:Potassium Chloride; D007444:Inulin; D008239:Lysine; D005944:Glucosamine