[Plastic metabolism in neurons altered according to the hypochromic type]

Ribonucleoprotein structures and condensed chromatin (CCh) have been studied electron cytochemically in neurons of the rat cerebral sensomotor cortex at their reversible (injection of aminazine) and irreversible (postmortem and posttraumatic processes) alterations according to the hypochromic type. For the hypochromic neurons, revealed after aminazine administration, increasing metabolic activity in their plastic apparatus is specific: intensification of the nuclear-cytoplasmic transport of RNA (decreasing amount of interchromatin granules and fibrils), when the acid synthesis is preserved, presence of small fibrillized clumps (SC), perichromatin fibrils (PChF); nucleolar structure is specific for the stage of active functioning. At the postmortem and posttraumatic alterations of the neurons according to the hypochromic type, the functional activity of the system DNA--RNA--protein in them is inhibited: mainly, the transcriptive activity of nuclei decreases (PChF, SC disappear and CCh appear). Combination of these processes with development of hydrolytic changes (nonidentified electron opaque material appears, CCh clumps and perichromatin granules undergo fibrillization, ribosomes decrease in their number) reflects certain irreversible lesions of hypochromic neurons.