Pharmacological testing of intracortical interneuronal connections.

The present study comprises an attempt to investigate the influence of acetylcholine on the functional connections of the cortical cells and their frequency characteristics. The multineuronal activity was recorded in the sensorimotor cortex of immobilized and freely moving rats, and was subsequently analyzed using the method of cross-correlational analysis. In the first series of experiments, the influence of the neuromediator, acetylcholine (ACh), and calcium chelation, ethyleneglycol tetraacetate (EGTA), on the functional characteristics of adjacent neurons during the iontophoretic application of these substances to cells of the sensorimotor cortex of unanesthetized immobilized rats was investigated.

The reactivity and interaction of neurons of the cerebral cortex of rats in the presence of the microiontophoretic action of acetylcholine in a model negative learning situation.

The activity of 46 pairs of neurons in the sensorimotor cortex of the brain of rats during multiple (up to 60) brief microiontophoretic applications of acetylcholine (ACh) was investigated by means of the method of multicellular recording, with subsequent division into separate impulse streams. It was demonstrated that neurons with high-amplitude spikes have a lower average frequency of discharges in comparison with low-amplitude [neurons]. It was established that cells located adjacent to one another exhibit responses in 63% of cases which are similar in their component makeup; the majority of these responses are inhibitory-excitatory and excitatory.