[Reaction of rats, formerly subjected to space flight, to immobilization stress].

The study of male Wistar rats flown on the biosatellite Cosmos-1129 showed that 7-10 hours after recovery they developed a distinct stress-reaction of blood cell elements (increased neutrophil and decreased lymphocyte counts) and the thymus (decreased thymocyte count). Despite this, the level of their reaction (as a percentage of the preflight values) to additional immobilization stresses was similar to that of controls. As a result, by the end of immobilization tests deviations from the physiological norm in the flown animals were greater and their reserve capabilities were lower than in the controls.