[Neuromediator adaptation of the cerebral cortex and brain stem structures after radiation exposure].

In experiments with male Wistar rats a decreased receptor binding of 3H-corticosterone and impairment of neuromediator adaptation in the brain structures responsible for the regulation of animal and vegetative functions were observed 6 months after the effect of external radiation (0.5 Gy) and a mixture of external radiation and 131I (6.5 microCi/kg).

[Intracerebral connections after administration of kainate into the caudal part of ventral sections of the medulla oblongata].

It was found that 1 day after unilateral destruction with kainate of neurons in the caudal ventral medulla unanesthetized animals showed disorders of arterial pressure control with a prevalence of hypertensive response. In 7 days after operation there was a decrease in the rate of neuronal uptake of serotonin and an increase in choline-, dopamine-, noradrenaline-, and glycinergic mediation in the basal hypothalamus and rostral ventral medulla, which characterize the functional state of synaptic formations in the brain stem structures connected to neurons in the caudal ventral medulla and involved in cardiovascular regulation.

[Glucocorticoid control of the mediator process in the brain structures during immediate adaptation].

In male rats with a high and low blood levels of corticosterone, the activity of serotonin-, dopamine-, noradrenaline-, glycine, GABA-, and cholinergic processes was shown to depend on the glycocorticoid content in the organism and receptor binding of 3H-corticosterone in different brain structures. The formation of adequate processes of neurotransmitter adaptation to a short-term vibration is only possible at a fairly high level of glycocorticoids in the organism.

[Modifying effects of neurotropin on post-radiation disorders of neuromediator processes in the autonomic function regulation centers].

In experiments on Wistar rats, it was shown that 6 months after exposure to ionizing radiation (X-radiation 0.5 Gy and intraperitoneal 131I 6.5 mCu/kg) the hypothyroid state was accompanied by changes in inhibitory and excitatory mediation that are characteristic of chronic radiation stress in cerebral structures responsible for regulation of autonomic and animal functions and a relative deficiency of the hypothalamopituitary-adrenocortical axis.

[The role of glucocorticoids in the post-vibration changes in inhibition mediation in the brain structures].

Low-frequency vertical vibration for 2 hours together with three-fold increase of glucocorticoids is accompanied by the disruption of typical relationships of neuromediator processes (norepinephrine- and serotoninergic mediation) as well as the reduction of the intensity of choline trapping with glucocorticoid perception. Glucocorticoid-related conformation changes in plasma membranes and a drastic increase of the cAMP level provide plasticity of both nonspecific (hypothalamus, raphe bluish sites and nuclei) and specific (Deiters' nuclei) structures. The relationships of neuromediator processes in different CNS structures depend on the content of glucocorticoids.