Dynamics of local blood flow in different regions of the hypothalamus in the sleep-wakefulness cycle.

In chronic experiments on cats, using the recording of local blood flow in different regions of the hypothalamus in the sleep-wakefulness cycle, it was found that during paradoxical sleep, the level of local blood flow in the posterior hypothalamus increased significantly, while at the same time in the anterior hypothalamus and in the preoptic region a sharp reduction takes place in local blood flow. In deep slow wave sleep the opposite pattern is observed: the level of local blood flow increases in the anterior hypothalamus and in the preoptic region, and decreases in the posterior hypothalamus. The conclusion is drawn that in one and the same sleep phase the diverse directionality of the changes in the level of local blood flow in the different regions of the hypothalamus must be associated with functional shifts in these structures, and the functional state of each of them in different phases of the sleep-wakefulness cycle is evaluated on the basis of this.