[Status of the synapses of the end brain of rats exposed to the factors of space flight].

Using electron microscopy, synapses of different structures of the rat end brain related to cognitive and motor acts (sensorimotor cortex, caudate nucleus) as well as memory and behavior (hippocampus) were examined. Rats were exposed to ionizing radiation, super-high frequency, hypoxia, hyperoxia, vibration and acceleration (applied separately or in combination) which have been traditionally in the focus of space and aviation medicine. Brain interneuronal junctions were found to be very sensitive to the above effects, particularly ionizing radiation and hypoxia. Conversely, synapses were shown to be highly resistant to short-term hyperoxia and electromagnetic radiation. When combined effects were used, responses of interneuronal junctions depended on the irradiation dose and order of application of radiation and other flight factors.