[Effects of ionotropic glutamate receptor channel blockers ON sleep-waking organization in rats]

The effects of non-competitive glutamate receptor antagonists on sleep-waking organization have been studied on Krushinskii-Molodkina rats having an inherited predisposition to audiogenic seizures and Wistar ones which are resistant to this action of sound. Two types of blockers of glutamate receptor open channels were used: selective blockers of NMDA receptors (memantine and IEM-1921) and blockers of mixed type, impacting both on the NMDA and Ca-permeable AMPA/ kainate receptors (IEM-1754 and IEM 1925). During the first 3 hours after administration of these glutamate antagonists the total or partial deprivation of fast-wave sleep was provoked. Additionally the selective NMDA receptor blocking drugs (memantine, IEM-1921) induced in the same period a significant increase of the representation of wakefulness at the cost of reducing of the total time of slow-wave sleep. These effects are most likely to be a consequence of the blockade of NMDA receptors responsible for the launch and maintenance of wakefulness, slow- and fast-wave sleep. In the same first 3 hours period after the administration of IEM-1754 and IEM-1925 the organization of sleep was not significantly affected. The evident reduction of wakefulness, total duration and increase of slow-wave sleep impact was observed, during the second three-hour period. It, apparently, can be caused by the blockade of AMPA/kainate receptors. The obtained results indicate the involvement of NMDA and AMPA/kainate receptors in the functioning of various parts of the sleep system of rats belonging to both lines.