[Changes in the ultrastructural indices of the axospinal synapses and in the reactions of long-term posttetanic potentiation in surviving slices of mouse sensorimotor cortex].

Electron microscopic and morphometrical methods were used to study axospinal synapses as well as reactions of continuous posttetanic potentiation of neurons in surviving slices of sensomotor cerebral cortex in white mice. Under the same experimental conditions electron microscopic and electrophysiological studies have established that the result of high frequency electrical stimulation consisted in the appearance of continuous posttetanic potentiation, and quantitative and morphometrical changes in the ultrastructure of axospinal synapses: decreased active zone, increased summary greatest width of the spine apparatus cisterns. A supposition is made that high frequency electrical stimulation results in changed content of Ca2+ in spine cytoplasm, which may be considered as a trigger factor influencing the changes of cable properties and synaptic efficiency of axospinal synapses at the initial period of the continuous posttetanic potentiation.