A. M. Kazennov

Effect of Total Hypothermia on the Fatty Acid Composition of Blood Phospholipids of Rats and Ground Squirrels and of the Light Irradiation on Chemical Processes in Lipid Extract

Effect of hypothermia on the fatty acid composition of rat and ground squirrel blood phospholipids is studied. Different reaction of these animals to cooling is revealed; in rats no changes were observed in the fatty acid composition of blood phospholipids, whereas in the winterhibernating ground squirrels there were significant changes in the content of individual fatty acids (FA). The content of monoenic acids in ground squirrels decreased almost by 50%, while the content of saturated acid (C18) and of polyenic acids C18: 2ω6 and C20: 4ω6 rose significantly. Such changes seem to be the mechanism that promotes maintenance of the organism viability under conditions of a decreased level of metabolism, heart rhythm, and body temperature and is evolutionary acquired. At the same time, the observed changes in the content of individual FA do not lead to sharp changes in such integrative parameters as the total non-saturation of phospholipids, which determines liquid properties of chylomicrons and other lipolipoprotein transport particles of the ground squirrel blood. There are studied absorption spectra of blood lipid extracts of rats and ground squirrels under effect of light as well as effect of light upon the FA composition of lipid extracts of these animals. The FA composition of lipid extracts has been established to remain practically constant, whereas the character of changes of spectra under action of light indicates the presence in the extracts of oxidation-reduction reactions. The obtained data allow suggesting that in the lipid extract there occurs cooperation of both the phospholipids molecules themselves and of them with other organic molecules, which makes it possible for fatty acids to participate in processes of transport both of electrons and of protons. This novel role of FA as a participant of the electron transfer might probably be extrapolated to chemical reactions (processes) occurring inside the membrane.

Changes of gas exchange parameters and of functional-biochemical properties of erythrocytes in dynamics of experimental anemia in rats

In experiments on male Wistar rats, in a specially constructed computerized installation, O2 consumption by the animals in comparison with changes of hematological, biochemical, and rheological blood properties is studied after anemization—acute blood loss (12–15% of the total blood mass). An increase of the O2 consumption by the organism and tissues by 18–28% has been revealed for the first 7 days after the blood loss, in spite of a pronounced decrease of hematocrit and of the amount of erythrocytes and hemoglobin in peripheral blood by 20–25% of the initial level. There was a 5–10-fold increase of the content of immature erythrocyte forms—reticulocytes and a progressive rise of cell acidic resistance, which is characteristic of young erythrocyte forms. An increase of O2 consumption at a decrease of the blood oxygen capacity (a low hemoglobin level) seems to be due to the more efficient transport and yield of O2 to tissues. At the 3rd and 7th day after the blood loss, activity of Na,K-ATPase has been found to increase by 60% and 20%, respectively. Analysis of the erythrocyte rheological properties has shown that the maximal firmness of aggregates (Uq) and the aggregation rate (1/T) decrease progressively beginning from 3 days after the blood loss; index of deformability (Imax) turned out to be elevated by 7–11%, probably due to an increase of the cell membrane elasticity. The conclusion is made that changes of erythrocyte rheological properties are interconnected with changes of the Na,K-ATPase activity and are directed at optimization of blood circulation in large vessels and the capillary network.

Changes of physiological and biochemical characteristics of rat erythrocytes after blood loss

In experiments on Wistar male rats, changes are studied of erythrocyte hematological, biochemical (activities of transport ATPases), and rheological properties (capability for aggregation and deformability) 7 days after bloodletting of 12–15% of the total blood mass. It has been shown that alongside with an elevation of erythrocyte volume and of the number of immature cells—reticulocytes, there was a statistically significant increase of Na,K-ATPase and Ca-ATPase activities in the whole erythrocytes and in their membrane preparations—ghosts, the increment of activity in the case of Na,K-ATPase being essentially higher in the whole cells. This indicates the appearance of an enzyme activator inside the erythrocytes. There are also revealed a decrease of firmness of erythrocyte aggregates, a deceleration of spontaneous aggregation, and an increase of index of erythrocyte deformability. The conclusion is made that changes of erythrocyte rheological properties are interconnected with changes of the Na,K-ATPase activity and are aimed at optimization of blood circulation in large vessels and capillary network.

Changes of Functional and Biochemical Blood Parameters in Wistar Rats and in Spontaneously Hypertensive Rats of the SHR Line during Short-Term and Long Tredmill Running

Effects were studied of single (40 min) or repeated exercise load (tredmill running, 14 m/min, 30 min) on the physiological and biochemical blood parameters characterizing the organism energetic and metabolic processes in complex experiments on male Wistar rats, on spontaneously hypertensive rats of the SHR line, and their normotensive control WKY. The mixed blood was used for determination of hematocrit, red blood cell count, hemoglobin concentration, level of 2,3-diphosphoglycerate (2,3-DPG) in red blood cells, erythrocyte acetylcholinesterase (AChE) activity, glucose, cholesterol, and triglyceride concentration, as well as plasma corticosterone level. To assess the erythrocyte population characteristics, the acidity erythrogram was determined. The weights of adrenal glands and spleen were evaluated. The single running induced a typical stress-response. After the repeated exercise load (the 7–14-day running), Wistar and WKY rats were well adopted to the load, unlike the SHR line rats that were practically not adapted to the repeated tredmill running.

Changes of Rheological and Hematological Parameters in Rats of Wistar and SHR Lines at Single and Multiple Tredmill Running

In experiments on rats of the Wistar line and on spontaneously hypertensive animals of the SHR line, a complex study was performed of rheological (deformability and aggregation properties) and hematological parameters of erythrocytes at the single (40 min) and multiple (20–30 min for 7 and 14 days) exercise load (a forced tredmill running at a rate of 14 m/min). It has been shown that rats of both lines respond to the single, sufficiently light exercise load by a manifestation of stress-reaction. After the repeated exercise load, all stress-induced changes were leveled and replaced by adaptation to this action in Wistar rats, but not in the SHR line rats. The hypertensive rats were characterized by a greater fatigue and refusal of the tredmill running; therefore, this load to them had to be shortened to 20 min. For the 1st week of running, no statistically significant differences in the studied parameters were found between rats of the Wistar and SHR lines; however, by the 14th day of training, substantial differences between these lines were noticed: the Wistar rats were easily adapted to the tredmill running, whereas the SHR animals completely refused to run. At the single running, the stress-polycythemia, an increased hematocrit, a decreased hemoglobin concentration per erythrocyte, an increased plasma corticosterone level, and changes of blood rheological characteristics were shown, the erythrocyte deformability and the spontaneous aggregation rate under the stress conditions being in the direct positive correlational dependence that was absent in control. The Wistar rat training to the exercise load for 14 days led to normalization of the parameters, which indicates a favorable effect of trainings on the animal health state.