[Modification of chemoreactive properties of neurons in the neocortex and hippocampus under the effect of electric stimulation of locus coeruleus].

Based on the findings of alterations in the chemoreactivity of neurons under conditioning and its possible significance for the formation of transient neuronal junctions, the authors investigated the influence of electrical stimulation of the Locus coeruleus upon the transmitter sensitivity of cortical and hippocampal neurons. The majority of neurons showed immediately after stimulation of the Locus coeruleus a different reaction to microiontophoretic application of acetylcholine, dopamine and glutamate than under normal conditions. Obviously there must have occurred qualitative changes because a superposition effect of the reactions following stimulation of the Locus coeruleus and application of the substances has rarely been observed. The release of noradrenaline provoked by the stimulation of the Locus coeruleus evidently leads to qualitative changes in the neurone texture, which may occur both inter- and intraneuronally.