[Ultrastructure of human cerebral cortical synapses: age-specific aspects].
The paper deals with electron microscopic studies of the cerebral cortex in human beings aged 70-80 years. The synapses show a decrease in the number of synaptic vesicles, their impaired distribution in the presynaptic process. There are changes in the mechanisms of interaction of synaptic vesicles and a presynaptic membrane. In the latter, the vesicles loose their discreteness, some of them are replaced by a fine-granular material. The joining of the vesicles and membrane is impaired. A part of active synaptic areas is transformed to desmose-like contacts. The findings are indicative of synaptic dysfunction.
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Bogolepov
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D002540:Cerebral Cortex / Q000502:physiology / Q000648:ultrastructure*; D006801:Humans; D008854:Microscopy, Electron; D008875:Middle Aged; D013569:Synapses / Q000502:physiology / Q000648:ultrastructure*; D009435:Synaptic Transmission / Q000502:physiology; D013572:Synaptic Vesicles / Q000648:ultrastructure