Morphologic changes in the sensomotor cortex in experimental neurosis

Disturbances of higher nervous activity (experimental neurosis) are attended with morphological changes of blood circulation in the sensorimotor area of the cerebral cortex, corresponding to distonic vascular disorders, as well as with hypoxic and neuroglial changes. Observed changes in the nervous tissue also reflect adaptive and defensive mechanisms of the brain (in rabbits).     

Structural bases of sensomotor integration in the cat's cerebral cortex

Connections of the somatosensory cortex surrounding the postcruciate fossa with the lateral region of the motor area (in the cruciate sulcus) were established by the Nauta-Gygax and Fink-Heimer methods and also by the retrograde horse-radish peroxidase transport method. A high degree of differentiation was found in the organization of transcortical sensomotor projections. The pyramidal, stellate, and inverted pyramidal neurons in the third layer of the cortex were shown to take part in the formation of these pathways. Results obtained by the experimental degeneration method combined with electron microscopy showed that afferentation from the first somatosensory area of the cortex reaches mainly cells in layers III and V. It is suggested that the influence of the association fibers on projection neurons in the motor area is transmitted either directly or through interneurons.M. V. Lomonosov Moscow State University. Translated from Neirofiziologiya, Vol. 13, No. 5, pp. 460–466, September–October, 1981.     

Effect of diazepam on the impulse activity of neurons in the sensomotor and visual areas of the rat cerebral cortex

Acute experiments on nonanesthetized curare-treated rats with the recording of the neuronal activity of the cortex were conducted; a determination was made of the threshold doses in which diazepam influenced the spontaneous and induced activity of the neurons of the sensory-motor and optic cortex. Diazepam proved to depress the spontaneous and induced activity of the neurons of the sensory-motor and optic cortex. Diazepam proved to depress the spontaneous and induced activity of the neurons of the sensory-motor cortex in considerably lesser doses than the neuronal activity of the optic cortex. It is supposed that the neurons of the anterior portions of the cortex were more sensitive to diazepam than the neurons of the limbic structures and the reticular formation.     

Effect of bradykinin and morphine on rat sensomotor cortex neurons]

As revealed in acute experiments on rats bradykinin applied microiontophoretically produced neuronal activation in the sensory-motor region of the rat brain cortex. Morphine applied iontophoretically prevented bradykinin effect. It is suggested that bradykinin interacts with opiate receptors in the cortical neurones.     

Dental receptor projections to the sensomotor zone of the rabbit cerebral cortex

Topic organization of the dental representation was studied in experiments on rabbits by the method of induced potentials. Every tooth proved to be locally represented in the sensory-motor zone of the brain cortex. These zones do not overlap in the case of stimulation of the threshold strength. Topic dental projection region occupies a territory including fields Par I, Praecag, Preacgr, and PC.     

Structural and functional reorganization of staphylococci and air-bearing system following experimental intratracheal introduction of pathogen

Morphological changes in the cells of the mucous membrane of the tracheo-bronchial system and in staphylococci under the conditions of intratracheal infection were studied. Different forms of interaction between the host cell and staphylococci, reflecting the organ specific properties and a wide range of compensation and adaptation reactions of eukaryotic and prokaryotic cells were revealed with the use of electron microscopy.     

Tryptophan uptake by glia and synaptosomes of rabbit cerebral cortex

The authors studied the engulfment of L-tryptophane-14C by gliacytes and synaptosomes of the rabbit cerebral cortex. The system of engulfment of the gliacytes was characterized by a high affinity to tryptophane (Km = 0.8 micrometer). Engulfment of tryptophane by synaptosomes had a lower affinity (Km = 50 micrometer). Psychotropic substances--chlorpromazine and imipramine produced an inhibitory influence on glial engulfment. The leading role of gliacytes in the trophic provision of the neurons and the normal course of neurodynamic processes is confirmed.     

Localization of ATPase in the cerebral cortex and its role in the functional activity of neurons]

By analogy of defensive conditioned reflex formation in rats using a cytochemical method, dependency of localization and concentration of the product of ATP-ase activity on neuronal and synaptic functional activity has been demonstrated. It corresponds to the notion that only a part of the cortical cells are simultaneously at the state of structural-functional activity. The experimental data demonstrate that the CNS excitation in the animals during the process of learning is connected with increasing ATP-ase activity in ultrastructures of the nucleolus, pericaryon and synapses of some neurons participating in the formation of trace processes in the brain.