[The combined action of head-down tilt hypodynamia and gamma irradiation on higher nervous activity in rats].

The paper deals with a combined effect of 30-day HDT and gamma radiation at a dose of 3 Gy on the higher nervous activity of the experimental rats. In the rats, the immobilization and isolation stresses induced by HDT are found to cause the development of pathologic aggressive reaction with the disorder of a species-typical pattern of an aggressive act and long-term change in animal social relations. The 30-day HDT disturbs the process of forming the motor-drinking differentiated conditioned reflex coming to a reduction of internal inhibition, generalization and sluggishness of a stimulation process. Functionally, these processes are reflected by a behavioral pattern shifting to stable stereotype impeding the formation of differentiated inhibition. Against HDT the unidirectional gamma radiation exposure increases this effect. In some cases, it leads to blocking the adaptational processes showing in the development of neurotic responses or deep, beyond the limits, inhibition.