BIOGENIC AMINES IN CULTURED NEUROBLASTOMA AND ASTROCYTOMA CELLS

The presence of biogenic amines in cultured cells of mouse neuroblastoma C-1300 (clone NB-2a) was suggested by fluorescence-microscope histochemistry. Incubation in media containing L-[(14)C]tyrosine and L-[(14)C]tryptophan for 24 h, followed by high-voltage electrophoresis, radiochromatogram scanning, and scintillation counting, confirmed the presence of [(14)C]dopamine, [(14)C]norepinephrine, [(14)C]epinephrine, [(14)C]serotonin, [(14)C]tyramine, and [(14)C]octopamine. Dopamine, norepinephrine, epinephrine, and serotonin were demonstrated spectrophotofluorometrically in concentrations, expressed as micrograms amine per milligram protein, of 1.19, 0.027, 0.038, and 0.148, respectively, for cells in a stationary growth phase. Fluorescence-microscope histochemistry also suggested the presence of biogenic amines in cultured astrocytoma cells (cell line C6). Spectrophotofluorometric assay of cells in a stationary growth phase demonstrated intracellular dopamine, norepinephrine, epinephrine, and serotonin in concentrations significantly lower than those of neuroblastoma cells.