[Patterns in the formation of cerebral damage and recovery from supralethal irradiation].

In experiments with rats it has been shown that dose-rate and radiation fractionation influence the dose dependence of early transient incapacity (ETI) and the development of tolerance to ETI. The authors discuss the possibility of interpreting the tolerance to ETI as a form of the cerebral damage displayed by the impairment of the brain response to radiation. A correlation has been revealed between the cerebral damage and recovery and repair of radiogenic damages to DNA.

[Regulatory disorders of locomotor functions in dogs during prolonged irradiation in a wide range of dose rates].

A biphase pattern of the development of locomotor disturbances, connected with the primary response and cerebral radiation syndrome, was demonstrated in experiments with dogs subjected to prolonged irradiation, just as it was observed after acute exposure. Dose thresholds for the development of these states were somewhat higher with the prolonged irradiation. The time of the appearance of disturbances increased due to the delay of achievement the dose threshold increase with dose-rate decrease, the time interval needed for the development of the corresponding pathological process being unchanged.

[Physiological characteristics of posture maintenance by dogs during immediate reaction to irradiation].

The ability of dogs to maintain a vertical posture during the first hours after irradiation at a dose of 10 or 80 Gy was investigated. Two experiments were performed. In the first experiment, during 5 hours after irradiation the vector stabilogram area, peak muscle efforts and sensorimotor coordination were measured 10 times every 30 min.

[Postradiation motor disorders in rodents as the equivalent of the clinical manifestations of a primary radiation reaction].

In experiments with albino mice it was found that during the first hours following gamma irradiation with doses of 10-80 Gy stability of implementation of loading and coordination tests was impaired and hard work endurance decreased. With doses exceeding 100 Gy, cerebral damages were stably manifested. There was a similarity between the postirradiation motor disturbances in animals of various species.

[The mechanism of the neuromotor disorders in the period of the primary reaction to irradiation].

In experiments with dogs it was shown that the impairment of the capacity of fulfilling some actions (e. g. high jumping, equilibration, racing) was maximum 4h after gamma-irradiation with doses of 10 and 40 Gy and did not coincide with vomiting.

[The phasic structure of early disorders of functional capacity following irradiation in rats].

In experiments with rats it was shown that an early decrease in physical efficiency after irradiation involves some partially mutually superimposed phases. Phases of excitation, hypokinesia and neurological disorders are identified in early transient inefficiency followed by phases of an early transient diminution of efficiency and a reversible disturbance of the accomplishment of the known operations. Simultaneously, there is a phase of an irreversible decrease of the informational capacity of CNS as well as the tolerance to early transient in efficiency upon repeated exposure.

[The rate of repair of a radiation lesion of the central nervous system during protracted and fractionated irradiation].

In experiments with fractionated and prolonged irradiation of guinea pigs and dogs it was shown that the recovery of CNS from acute radiation affection may be approximated, for different animal species, by an exponential function at a rate of 0.02 h-1 and a half-life period of approximately 30 h.

[Various physiological characteristics of primary radiation reaction and its apomorphine model].

Experiments were performed on 52 dogs exposed to irradiation at a dose of 5-80 Gy or injected with 0.02-0.5 mg/kg apomorphine.