[Electrophysiological study of the connections between the nuclei in the medial and lateral zones of the respiratory center].

Experiments on anesthetized cats were made to study evoked electrical responses of the neurons of the ventral and dorsal respiratory nuclei to single stimulations of the previously described inspiratory and expiratory sites of the giant cell nucleus. The majority of the respiratory neurons responded with evoked activity. Mono- and polysynaptic responses were obtained in both respiratory and reticular neurons, which indicates the existence of the relations of varying degree of complexity between the structures of the medial and lateral zones of the respiratory center, thereby making it possible to explain the mechanism of the recovery of respiratory movements during stimulation of the inspiratory sites of the giant cell nucleus.

[Role of reticular neurons of the medulla oblongata in the organization of the respiratory act].

There are 3 groups of reticular neurons in the respiratory center. Of these, one group is primarily localized in the medial zone, providing for the principal relation of the center with afferent impulses from the respiratory apparatus and chemoreceptors. The other one is in the inspiratory and expiratory sites, participating in the integration of signalization and in the activities of the effector mechanisms of the center.

[Correction of respiratory disorders by electric stimulation of various structures of the respiratory center].

Impulse activity of respiratory neurones and respiration during electric stimulation of the inspiratory and expiratory sites of the respiratory center was studied in cats anesthetized with nembutal. The study was made with an object of imposing a new rhythm on these sites and of recovering respiratory function. It has been established that stimulation of the inspiratory and expiratory sites of the giganto-cellular nucleus and of some structures of the solitary tract nucleus enables one to impose the new rhythm on the respiratory neurones of the ventral and respiratory nuclei and on respiration as well as to renew the respiration arrested.

[Reciprocal connections of respiratory center nuclei].

The reactions of 181 respiratory neurons of solitary and ambiguous nuclei were studied on 64 cats in the course of stimulation of inspiratory and expiratory zones of gigantocellular nuclei. A study was also made of the reactions of 224 reticular and 9 respiratory neurons of these zones during stimulation of solitary and ambiguous nuclei. Various reactions were recorded in response to the stimulation.

[Effect of stimulating the medial and lateral zones of the respiratory center on the electrical activity of the diaphragm, intercostal muscles and phrenic neurons].

Experiments on cats showed that the nucleus of the solitary tract displayed zones whose stimulation provoked separately stimulation or inhibition of the electrical activity of the phrenic neurons and the diaphragm. Stimulation in the nucleus ambiguus of such zones caused stimulation and inhibition of electrical activity of the intercostal inspiratory muscles. In stimulation of the corresponding zone in the giant cell nucleus the electrical activity of both groups of the inspiratory muscles proved to change.