[The retroactive action of paradoxical sleep deprivation and immobilization stress on the mechanisms of memory and passive avoidance in rats].

Influence was studied of 48-hours deprivation of paradoxical sleep (DPS) and immobilization stress on conditioned reaction of fear and security--components of passive avoidance conditioned reflex (CRPA), with simultaneous studying of vertical, horizontal activity, grooming reactions and defecations in an illuminated chamber. The obtained results allow to conclude that DPS inhibits reproduction of memory traces of fear reaction but intensifies the process of learning and activity of memory traces of security reaction. Depending on condition of CRPA elaboration, DPS may disturb or, on the contrary, prolong preservation of passive avoidance. It has been found that the immobilization stress does not influence CRPA preservation and does not weaken the reaction of fear but increases the horizontal activity. It is suggested that the observed changes in behaviour and trace processes are connected with disturbance of sensory informational homeostasis of the nervous system at DPS.