ABSTRACT
By the open-field behavior, August rats were more resistant to acute hypoxia than Wistar rats. Hypoxic activation of the immune system was more pronounced in August rats. As differentiated from Wistar rats, the stress-limiting NO system in August rats was not suppressed during hypoxia. The effectiveness and resistance of this system to hypoxia were higher in August rats. Behavioral changes in Wistar rats under hypoxic conditions were accompanied by activation of HSP32 synthesis in blood leukocytes. This protein serves as an indicator of oxidative stress (i.e. adverse factor in hypoxia). August rats were more resistant to behavioral disturbances in hypoxia than Wistar rats. HSP32 synthesis in leukocytes from August rats was not impaired under hypoxic conditions. Our results indicate that variations in HSP32 synthesis in peripheral blood leukocytes can be considered as a matter of for resistance to acute hypoxia.
Subject(s)
Hypoxia/physiopathology , Leukocytes/metabolism , Animals , Behavior, Animal , Heme Oxygenase (Decyclizing)/metabolism , Leukocytes/physiology , Male , Motor Activity , Nitric Oxide/metabolism , Organ Size , Rats , Rats, Inbred Strains , Rats, Wistar , Signal Transduction , Species SpecificityABSTRACT
The aim of the study was to compare the protective effects of adaptation to altitude hypoxia (AH) on neurodegenerative brain disorders (NBD) induced with infusion of beta-amyloid peptides (Abeta) into the brain (imitation of Alzheimer's disease) of rats belonging to two species: Wistar rats (WR) and August rats (AR). Previously it was shown by the authors that WR were less resistant to memory function impairment and open-field activities, induced with Abeta infusion compared with AR. This study showed that preliminary AH significantly restricted brain function impairment induced by Abeta in WR, so AH demonstrated the protective effect in WR. In contrast, in AR preliminary AH provoked those impairments induced by Abeta. The AH protective effect in WR was associated with activation of stress-limiting systems (antioxidant system, NO system). Lack of AH protective effect in AR was associated with lack of activation of these systems in these rats. Thus, the different AH effects on NBD development in WR and AR are obviously determined by hereditary peculiarities of stress-limiting systems in WR and AR.
Subject(s)
Adaptation, Physiological/physiology , Brain/pathology , Hypoxia/genetics , Immunity, Innate/physiology , Neurodegenerative Diseases/pathology , Animals , Male , Rats , Rats, Inbred Strains , Rats, WistarABSTRACT
The effect of preadaptation to non-damaging emotional stress on the synthesis of HSP70 (stress-limiting factor) in peripheral blood leukocytes was studied in experiments on August and Wistar rats characterized by different sensitivity of the gastric mucosa to stress-induced injury. It was found that preadaptation improves stress resistance of Wistar rats characterized by lower innate resistance to acute mental stress and activates HSP70 synthesis in blood leukocytes. In August rats characterized by higher resistance to acute stress, adaptation reduced the resistance to stress-induced injuries, which was accompanied by the absence of activation of HSP70 synthesis in leukocytes compared to the level observed in nonadapted rats during acute stress. Thus, the intensity of HSP70 synthesis in peripheral blood leukocytes can serve as a marker of changes in animal resistance to acute stress caused by adaptation to non-damaging stress exposures and probably to other environmental factors.
Subject(s)
Adaptation, Physiological/physiology , HSP70 Heat-Shock Proteins/blood , Leukocytes/metabolism , Stress, Psychological/blood , Animals , HSP70 Heat-Shock Proteins/biosynthesis , Male , Rats , Rats, Inbred Strains , Rats, Wistar , Stomach Ulcer/etiologyABSTRACT
Preadaptation of cultured HT22 mouse hippocampal neurons to oxidative stress prevented cell damage induced by severe oxidative stress. This protection manifested in a decrease in metabolic disturbances in neurons. Adaptation of neurons to oxidative stress was accompanied by accumulation of HSP32 and HSP70. HSP synthesis inhibitor quercetin abolished the protective effect of adaptation under conditions of oxidative stress. Activation of HSP70 synthesis in neurons is an important mechanism for adaptive protection of cells.
Subject(s)
HSP70 Heat-Shock Proteins/metabolism , Heat-Shock Proteins/metabolism , Hippocampus/metabolism , Adaptation, Physiological , Animals , Cell Line , Hippocampus/cytology , Hippocampus/drug effects , Hydrogen Peroxide/toxicity , Mice , Neurons/drug effects , Neurons/metabolism , Oxidative StressABSTRACT
The resistance of August rats to ulceration of the gastric mucosa induced by acute emotional stress was higher than in Wistar rats. August rats exhibited not only more potent activation of the protective nitric oxide system and mobilization of the immune system, but also increased synthesis of cytoprotective heat shock proteins HSP70 in blood leukocytes under stress conditions. Our results indicate that HSP70 protein synthesis in blood leukocytes during stress reflects organism's resistance to stress and, probably, to other adverse factors.