Interaction between the thalamic nucleus and preoptic area neurons.

The thalamic reticular nucleus which is known to delineate the dorsal thalamus stipulates development of inhibitory processes in the thalamo-cortical neurons that is necessary for generating slow (8-12 Hz), high-amplitude electric activity in this system. It was demonstrated that majority of preoptic area neurons get activated during slow-wave sleep. Activation of neurons in the anterior hypothalamus and preoptic area during slow-wave sleep and synchronization of the brain electric activity was demonstrated. The study was aimed at clarifying the relationship between the thalamic reticular nucleus and the preoptic area neurons. Under acute conditions experiments were carried out on mature cats. It was shown that blockade of preoptic area neuron activity during mesencephalic reticular formation stimulation and the fact that on the background of mesencephalic reticular formation stimulation thalamic reticular nucleus stimulation elicited preoptic area neurons activation must be in part stipulated by the fact that thalamic reticular nucleus activation leads to suppression of mesencephalic reticular formation neuron activity.