[The effect of altered oxygen partial pressure on the resisitance to hypoxia and expression of oxygen-sensitive genes in Drosophila melanogaster].

As a result of resistance test to hypoxia of Drosophilas melanogaster of Oregon strain, we identified a high resistance (Group II) and low resistance (Group III) subpopulations of flies. Flies from groups II and III were incubated in a constant normobaric hypoxia (Po2=62-64 mm Hg) for 10 generations. A highly resistant group (Group IV) were exposed to a shortterm anoxia (Po,=1,5 mm Hg, 5 min) every generation. Larvae from Groups II, III, and IV demonstrated significantly elevated levels of Sir and CG 14740 expression. Larvae from Group II had a significantly higher expression of CG 14740 compared to group III. The restitution time after exposure to anoxia was significantly reduced in Group II (on 31% of the control values) Our results suggest that long-term adaptation to low oxygen partial pressure of highly resistant Drosophila significantly reduces the time of restitution and increases the expression of Sir2 and CG14740 genes.

[Dosed normobaric hypoxia as a non-medication approach of stimulation of physiological regeneration of liver parenchyma].

The investigation was devoted to studying the effects of different modes of dosed normobaric hypoxia on the changes in morphometric indexes of functional activity and physiological regeneration of liver parenchyma in young rats. It was shown, that in rats exposed to hypoxic gas mixture (10% O2), the amount of karyonucleus and binuclear hepatocytes, nucleocytoplasmic and nucleolar-nuclear correlation increased. The changes in these indexes appeared to be more intensive when dosed normobaric intermittent hypoxia was administered with alternation of deoxygenation and reoxygenation periods. We believe that dosed normobaric hypoxia increases the functional activity and physiological regeneration of liver parenchyma.

[Influence of food restriction on the biomechanical properties of the tibia in male rats of different age].

The changes of tibial bones biomechanical properties after 28 daily 40% declines of calorie content of feed and subsequent period of proceeding in a food ration were study in young and adult rats.28 day diminishing of calorie content of day's ration decline of bone mass, load capacity, stiffness, energy of elastic deformation of tibial bones. The indexes of biomechanics properties of bones were normalized after 28 daily period of proceeding in the ordinary ration of feed.

[Effect of oxygen deprivation on photosensitivity and thermostability of Drosophila].

There are certain distinctions in firmness to the high temperature and photo sensitiveness between highly and low steady to the hypoxia action of flies. Flies of line Conton-S after preadaptation to hypoxia acquired more firmness to the high temperature. Most of flies in line Uman, who are high-steady to the action of hypoxia, had positive phototaksis. It goes to show that firmness to the high temperature and phototaksis flies Drosophila are genetically programmed and passed on an inheritance.

[The model of hypokinesia in rats and preventing its negative effects].

The special container for modeling of long-term hypokinesia state in rats was developed. Such construction allows us to examine simultaneously hypokinesia and its negative influence correction by gas mixture regulated with different oxygen partial pressure.

[The modeling of experimental osteopenia in rats and development of prophylaxis technology]. / Modeliuvannia eksperymental'noï osteopeniï ta rozrobka tekhnolohiï ïï profilaktyky u shchuriv.

An appliance for hind limb unloading in rats and the technology for preventing of inactivity osteopenia have been developed.

[Effect of oxygen deprivation on the development of osteodystrophy caused by the load deficit]. / Vplyv kysnevoï depryvatsiï na rozvytok osteodystrofiï pry defitsyti navantazhennia.

The subject of the study was influence of gas mixture (GGS) with low Po2 on biomechanical properties of femoral and tibial bones in rats after hind-limb unloading. Experiments were performed in two different age groups (three month and six month) rats. It is shown that biomechanical properties of bone tissue in young rats, inhaling atmosferic air, under the influence of 28 days hind-limb unloading deteriorate essentially in comparison with adult rats. The biomechanical indexes of femoral and tibial bones in three month age rats close to control value after periodical inhaling of GGS. In six month age rats normalizing action of low Po2 not so essential. Thus bone tissue of young rats is more sensitive to different pathogenetic action than in adult rats. Such difference may be connected with retard of remodelation of bone tissue in adult rats.

[The effect of measured hypoxia on the development of situational osteopenia]. / Vplyv dozovanoï hipoksiï na rozvytok sytuatsiinoï osteopeniï.

The influence of gas mixture with low PO2 (90-110 mm Hg) on calcium-phosphorus metabolism and biomechanical properties of femur bones at rats, who were kept under condition of hind-limb unloading during 28-days, has been studied. Loss of calcium and phosphorus during a day was less in rats, who was received gas mixture with lower PO2, than rats who was kept in condition of hind-limb unloading only. Hypoxic gas mixture stabilized mechanical properties of bones tissue in femoral bone of rats. Gas mixture with lower pressure of oxygen retard development of osteopenia and may be used with other corrective methods for situation osteopenia prevention.