Ultrastructural aspects of synaptic adaptability in human brain.

The ultrastructure of synapses in human brain which died with ischemic heart disease in various time after ischemic injury showed that the whole range of symptoms of compensatory character appears together with degenerative changes. The most important changes of presynaptic membrane consist of pinocytous invagination. Tubular structures in region of synaptic contact as well as on the surface of small invaginal axonal branches, dendrites and small spines are also found. We assume that plastic rebuilding of synapses have compensatory significance.