The occurrence in the human brain of neurons with strongly negative-charged proteoglycans

The occurrence of neurons with strongly negative-charged surface-coats was confirmed in the human brain. Cerebral cortical tissue pieces (Area 19 of Brodmann), which had been removed in surgery from a 45-year-old Japanese man with meningioma were fixed with formalin. These specimens were cut into sections, stained with fine cationic iron colloid at pH value 1.0-2.0, treated for Prussian blue reaction, counter stained with carbolthionin, and observed with a light microscope. The observations indicated that some large-sized pyramidal cells in the ganglionic lamina were strongly negative-charged or coated with sulfated proteoglycans, though where these cells projected to could not be determined.