[Age changes of structural state of synaptic membranes of brain].

In the brain synaptic membranes from old rats (24-26 months) in comparison with the mature ones (6-7 months) an increase was shown in disintegration rate with DDS Na, mobility of 5-, 16-doxyl-stearate spin probes and in thermosensitivity of acetylcholinesterase. The total number of SH-groups decreased. While protein composition remained constant lysophosphatidylcholine and saturated fatty acid content in old animals increased. The age-dependent structural rearrangement of synaptic membranes is suggested.