Efficacy of green tea extract in two exercise models.

Oral administration of green tea extract in a dose of 6 mg/kg twice a day (before and after exercise) over 2 weeks significantly increased swimming times on week 1 and 2 in comparison with control animals receiving water. The 7-day and final exhaustive running in rats was accompanied by a significant decrease in spleen weight and iron serum levels associated with developed reticulocytosis. Administration of green tea extract in a dose of 12 mg/kg once a day (before exercise) for 2 weeks did not affect the duration of the running, but prevented the decrease in serum iron and spleen weight, that, along with a significantly increased concentration of reduced glutathione in erythrocytes, can indicate a normalizing effect of green tea extract on hemopoiesis and stimulating effect on the antioxidant system of erythrocytes.

[Repeated action of hyperbaria on rat blood system].

There are considered reactions of male Wistar rat blood system to repeated action of nitrogen-oxygen hyperbaria (pressure 0.5 MPa, density of gas medium 6 g/l, pO2 = 0.02-0.03 MPa). Rats were placed into a barochamber for 5 h 24, 72, and 120 h after the first exposition (control in air without the increased pressure). Parameters of red blood were studied and the general state of the animals was estimated. It has been established that after the first hyperbaria séance the stress-reaction develops in rats with all objective stress parameters (level of corticosteroids and content of ascorbic acid in adrenals). At repeated exposure after 24 h the almost complete normalization of all stress parameters was observed, except for the increased hemoglobin content in plasma as a result of impair of permeability of erythrocytic membranes. After repeated actions 72 and 120 h later, the stress parameters manifested again. After exposure 120 h later, the general state of animals was sharply deteriorated they did not move in the "open" field, could not be hold on a horizontal bar, and mainly were lying. The performed control with the immobilization stress showed that after the initial stress-reaction the rats were recovered completely and at repeated exposures no changes were observed in the blood system and in the general state of the animals. We belive that the hyperbaria-produced stress is connected with difficult breathing under pressure. Thereby, the repeated action of hyperbaria is a harmful factor and habituation to it does not occur.

[Hyperbaria and stress].

Causes of the appearance of stress-reaction at action of hyperbaira on the organism were studied on rats. It has been established that at the 5-h action of gas mixtures (oxygen-nitrogen and oxygen-argon) under pressure 0.35 and 0.5 MPa and partial pressure of oxygen 0.02-0.03 MPa in the chamber of the volume of 300 1 there is obviously manifested stress confirmed by the corresponding markers. The appearance of stress was connected with the gas mixture density that amounts to 6 g/l, which interferes with respiration mechanically. Use of helium at the same pressure of the gas mixture did not cause stress, as its pressure did not exceed the normal air density. On the other hand, use for respiratory mixtures of elegas (SF6) with density of 6 g/l at the normal pressure produced obvious stress. No difference was revealed in action of nitrogen, argon or elegas at equal density. Thus, use of high pressures needs light gases (helium, hydrogen, neon) that have low density.

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

In experiments on Wistar male rats, on a specially constructed computer installation, O2 consumption by the animals in comparison with changes of hematological, biochemical, and rheological blood properties is studied after anemization--acute bloodletting (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 bloodletting, 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 7th day after the bloodletting, activity of Na,K-ATPase has been shown 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 bloodletting; index of deformability (I(max)) 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 to 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 of Wistar male rats, changes are studied of erythrocyte hematological, biochemical (activitities 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 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 directed to optimization of blood circulation in large vessels and capillary network.

Endogenous plasma Na,K-ATPase inhibitory activity and digoxin like immunoreactivity after acute myocardial infarction.

PURPOSE OF INVESTIGATION: The aim was to look for the presence of circulating factor(s) with Na,K-ATPase inhibitory properties and digoxin like immunoreactivity in patients after acute myocardial infarction. DESIGN: Venous blood samples were obtained when the patients were admitted and different methods were used to monitor the plasma concentrations of factor(s) with properties of digitalis. SUBJECTS - These were 26 patients of both sexes (mean age 57.7 years, range 40-72) during the first 24 h of a first transmural acute myocardial infarct, 11 male patients with unstable angina pectoris (52.5 years, 45-67), and 18 healthy male controls (25 to 50 years). MEASUREMENTS AND MAIN RESULTS: There was significant inhibition of ouabain sensitive Na,K-ATPase in intact erythrocytes in patients with myocardial infarction [1.4(SEM 0.15)mumol Pi.mg-1.h-1] compared with patients with unstable angina pectoris [3.1(0.4), p less than 0.01] and healthy controls [3.4(0.25), p less than 0.01]. In myocardial infarction complicated by ventricular fibrillation (n = 5) Na,K-ATPase activity was significantly lower than in the other 21 patients [0.95(0.2) and 1.55(0.11) mumol Pi.mg-1.h-1 respectively, p less than 0.05]. There was no change in erythrocyte Na,K-ATPase activity in myocardial infarction complicated by acute pulmonary oedema, nor was there any difference in activity in erythrocyte ghosts obtained from the patients with myocardial infarction v healthy controls, at 0.47(0.13) v 0.50(0.02) mumol Pi.mg-1.h-1. Boiled plasma supernatants obtained from the patients with myocardial infarction inhibited Na,K-ATPase in erythrocytes from healthy subjects. This inhibitory effect was antagonised by antidigoxin antibody. Plasma inhibitory potency was correlated with erythrocyte Na,K-ATPase activity in the patients with myocardial infarction (r = -0.65, p less than 0.001, n = 23). There was a 2.5-fold increase in plasma digoxin like immunoreactivity in the patients with myocardial infarction [1.65(0.5) ng.ml-1] using DELFIA fluoroimmunoassay as compared with five healthy controls [0.04(0.12), p less than 0.05] and nine patients with unstable angina [0.48(0.11), p less than 0.05]. There was no difference in plasma digoxin like immunoreactivity in myocardial infarction complicated or not by ventricular fibrillation, but there was very low digoxin like immunoreactivity in patients with myocardial infarction complicated by acute pulmonary oedema [0.26(0.08) ng.ml-1, n = 7]. There was no correlation between plasma digoxin like immunoreactivity and either plasma Na,K-ATPase inhibitory potency or erythrocyte Na,K-ATPase activity. CONCLUSIONS: The results show that plasma factor(s) with some of the properties of digitalis are increased in acute myocardial infarction.

Rheologic properties of mammalian erythrocytes: relationship to transport ATPases.

Rheologic properties of erythrocytes and activities of their Ca(2+)-ATPase and Na+, K(+)-ATPase were analyzed together with standard erythrocyte values in seven mammalian species (man, rat, mouse, rabbit, hamster, guinea pig and dog). The number of erythrocytes in the blood of animals investigated correlated inversely with the mean cell volume (MCV) (r = -0.936, P = 0.002) and the mean cell hemoglobin content (MCH) (r = -0.923, P = 0.003). MCV and MCH also showed a high direct correlation with each other (r = 0.907, P = 0.005). The maximal erythrocyte deformability (DImax) measured with ektacytometry was inversely proportional to the MCV and MCH (r = -0.854, P = 0.014, and r = -0.940, P < 0.002, respectively). The MCV was also linearly related with the Na+, K(+)-ATPase activity (r = -0.791, P = 0.034). The major parameters of osmoscan (O' and Omax) and their derivatives (O'-Omin, Omax-Omin) were shown to be in a direct correlation with each other and with the activity of Na+, K(+)-ATPase in the whole erythrocytes except for the rabbit Na+, K(+)-ATPase. The activity of Ca(2+)-ATPase in the whole erythrocytes significantly correlated only with the O' and O'-Omin values. Thus, the activities of transport ATPases in mammalian red cells seem to be adjusted to the level required to maintain particular rheologic properties of the cells of one or other species.

Species variability of erythrocyte transport ATPases in mammals.

Na+, K(+)-ATPase, and Ca(2+)-ATPase in whole erythrocytes from five species of mammals (rat, mouse, guinea pig, golden hamster, rabbit) after cell treatment with Tween 20 (7.5 mg/ml) varied over a wide range: from 3.0 +/- 0.9 mumol Pi/hr/ml cells in rabbit to 27.3 +/- 4.9 mumol Pi/hr/ml cells in mouse for Na+, K(+)-ATPase and from 8.0 +/- 1.6 mumol Pi/hr/ml cells in hamster to 47.2 +/- 4.9 mumol Pi/hr/ml cells in mouse for Ca(2+)-ATPase. Differences were less pronounced in red cell ghosts. Fatty acid and phospholipid compositions of erythrocyte membranes were similar for all species. Nevertheless, the activity of Ca(2+)-ATPase in ghosts significantly correlated (r = -0.884) with the ratio of PC + SM/PE + PS in red cell membranes. Rabbit membranes had the lowest content of arachidonate. Rat hemolysate activated Na+, K(+)-ATPase in the ghosts from the animals of any species investigated, whereas the enzyme activation by the homohemolysate was characteristic only of the rat, mouse, and guinea pig ghosts. The data obtained suggest that there are differences in both activity and intracellular control of transport ATPase in erythrocytes of different mammals.

External acetylcholinesterase of the brain in the ontogenesis of maturely and immaturely born rodents.

The fraction of external acetylcholinesterase (AChE) in various divisions of the brain was studied in maturely and immaturely born rodents. It was established that in maturely born rodents (guinea pigs) the fraction of external AChE in all the investigated division of the brain is the same by the time of birth of the animals as in the adults. In immaturely born rodents (white rats), by the moment of birth the fraction of external AChE is significantly higher than in adults. As the brain matures there is a decrease in the proportion of external AChE, most pronounced in the forebrain. It is suggested and experimentally confirmed (in experiments with detergents) that the decrease in the fraction of external AChE is associated with a strengthening of the fixation of the enzyme in the membrane.

[The effect of the membrane skeleton of non-nucleated erythrocytes on the properties of transport ATPases]. / Vliianie membrannogo skeleta bez''iadernykh éritrotsitov na svoistv transportnykh ATFaz.

Removal of spectrin and other proteins of membrane skeleton from rat erythrocyte membranes resulted in a significant loss of Na,K-ATPase and Ca-ATPase activities, and even more of respective phosphatase activities. At the same time the modulating influence of ATP and Ca2+ on the enzymes disappeared. These ATPase activities were reconstituted by addition of concentrated spectrin to spectrin-depleted membranes. The activating influence of Ca2+ on ouabain-resistant and ouabain-sensitive phosphatases in ghosts could be discovered only in the presence of ATP. The highest activities of both the phosphatases were revealed when both ATP (0.5 mM) and Ca2+ (10-30 mM) were present simultaneously in the incubation medium. These data show that the functioning of transport ATPases in non-nuclear erythrocyte membranes is related to the membrane skeleton: regulating influence of intracellular ATP and Ca2+ on enzymes seems to be realized through the proteins of the skeleton.

[Na K ATPase activity and pulmonary hemodynamics in the development of arterial hypertension]. / Aktivnost' Na,K-ATFazy v éritrotsitakh i sostoianie gemodinamiki malogo kruga krovoobrashcheniia pri formirovanii arterial'noi gipertonii.

A total of 116 subjects with borderline hypertension, 67 relatives of normotensive probands and 29 relatives of hypertensive probands were examined. The activity of Na,K-ATPase in the red blood cells and pulmonary hemodynamics were studied by kinetocardiography. The normotensives with a family history of essential hypertension and subjects with borderline hypertension were found to have elevated pulmonary systolic pressure. The changes were coupled to lower erythrocyte Na,K-ATPase activity, which seems to suggest that endogenous ouabain-like factor that inhibits the enzymatic activity is present in plasma.

[Ionic homeostasis and erythrocyte deformability in patients with primary arterial hypertension]. / Ionnyi gomeostaz i deformiruemost' éritrotsitov u bolnykh s pervichnoi arterial'noi gipertenziei.

Erythrocyte Na, K-ATPase was examined for its activity and relation to the concentration of the complexon EDTA in 39 patients with arterial hypertension (AH), 12 subjects with borderline hypertension, and 18 normotensives. The ionic composition and deformability of erythrocytes were also studied. As compared to normotensives, the patients with Stage I AH displayed a significantly lower activity of erythrocyte Na, K-ATPase, which may suggest that there is an enzyme inhibitor in the blood of the patients. According to the enzyme activity, the patients with Stage II AH were divided into two subgroups: 1) those with a lower activity and 2) those with a higher activity than healthy subjects. The patients with a Stage II AH who showed a lower activity of Na, K-ATPase exhibited a more elevated erythrocyte sodium level, whereas those who had a high activity of the enzyme displayed a decreased erythrocyte deformability. In addition, a positive correlation between erythrocyte sodium concentrations and Na, K-ATPase activity, as well as erythrocyte deformability was found in normotensives, whereas a negative correlation was established in AH patients.

[Possibilities for Ellman reaction application in the presence of detergents]. / Vozmozhnosti primeneniia reaktsii Ellmana v prisutstvii detergentov.

Triton X-100, triton X-305, twin-80 and sodium deoxycholate in definite concentrations lower the colour intensity of the solution which contains the product of the Ellman reaction. In the case of triton X-100 the colour disappearance is due to resynthesis of the Ellman reagent from 5-thio-2-nitrobenzoate with the presence of detergent in the concentration which is higher than the critical concentration of micelle-formation.

[The activity and properties of Na,K-ATPase in the erythrocytes and the Na-pump inhibitor in the plasma of subjects with borderline arterial hypertension]. / Aktivnost' i svoistva Na,K-ATFazy v éritrotsitakh i ingibitor Na-nasosa v plazme u lits s pogranichnoi arterial'noi gipertenziei.

The activity and properties of Na,K-ATPase in erythrocytes and their membrane preparations (ghosts) from 34 subjects with borderline hypertension and 21 normotensive controls were studied. The Na,K-ATPase activity was found to be by 43% lower as compared to control group. No changes in the Na,K-ATPase activity were revealed in the ghosts of borderline subjects. This suggests that the plasma of borderline subjects contains an inhibitor of Na,K-ATPase. The plasma level of sodium pump inhibitor was measured in 21 borderline hypertensive subjects. It was found to be about 19% compared with the control group. These findings suggest presence of Na,K-ATPase inhibitor in the plasma of borderline subjects, which is likely to be involved in the development of hypertension.

[The effect of hypothermic stress on Na,K-ATPase activity in rat erythrocytes]. / Vliianie gipotermicheskogo stressa na aktivnost' Na,K-ATFazy v éritrotsitakh krys.

After 3-hr cooling stress, the activity of the erythrocytes' Na,K-ATPase was decreased by 28.9 per cent in rats, its complete restoration occurring within 24 hours after the stress. Possible reasons and factors inducing a disorder in the enzyme activity under conditions of hypothermia, are discussed.

[Age-related changes in Na,K-ATPase activity of the plasma membrane of kidney cells and erythrocytes in spontaneously hypertensive and normotensive rats]. / Vozrastnye izmeneniia aktivnosti Na,K-ATFazy plazmaticheskoi membrany kletok pochki i éritrotsitov u spontanno gipertenzivnykh i normotenzivnykh krys.

The Na,K-ATPase activity and sensitivity to ouabain in kidney and erythrocytes of spontaneously hypertensive (SHR) and normotensive rats (Wistar-Kyoto and Wistar) of different age, were studied. The enzyme activity in cortex of kidney of SHR and WKY of any age were lower than that in cortex of Wistar rats. In 1.5-month rats the enzyme activity in cortex of SHR was lower than that of WKY and higher in 3-month animals. Weanling rats of every line had a decreased sensitivity of Na, K-ATPase to ouabain in cortex and medulla of kidney as compared to erythrocyte enzyme but with ageing it increased and reached the erythrocyte level. The possible role of Na,K-ATPase in pathogenesis of primary hypertension is discussed.

[Aminobenzoic acid derivatives as specific inhibitors of cyclic nucleotide phosphodiesterase in the rat uterus]. / Proizvodnye aminobenzoinoi kisloty kak spetsificheskie ingibitory fosfodiésterazy tsiklicheskikh nukleotidov matki krys.

It is shown, that p-aminobenzoic acid and its derivatives (p-acetylaminobenzoic acid and p-aminobenzoic acid hydrazide) in the concentration of 10(-6) M are the potent inhibitors (40% below the control specimens) of the phosphodiesterase activity of cyclic nucleotides in the soluble fraction of the adult rat uterus. These drugs exerted no action on the adenylate cyclase activity in membrane fractions. The inhibition is only specific to the uterus enzyme and is not revealed for other tissues. The inhibition is found to be of incompetitive character Ki for p-aminobenzoic acid hidrazide being equal to 3.2 microM.

[The effect of aminostimil on the regulation of sexual function in rats]. / Vliianie aminostimila na reguliatsiiu polovoi funktsii u krys.

The effect of aminostimil: a synthetic drug of the acylhydrazide group, was studied in white rats. Aminostimil decreased the uterus weight but did not interfere with estrogen positive action in ovariectomized (OVX) rats, although it increased the FSH level, abolished the inhibitory effect of estradiol on the FSH secretion and did not change the secretion of the LH. Aminostimil induced accumulation of GnRH in the preoptic area and median eminence area in intact female and male rats, LH concentration in the blood plasma but decreased. The data obtained suggest that the antiestrogenic effect of aminostimil is due to inhibition of the GnRH secretion from the hypothalamus into the portal blood.

[The seasonal dynamics of erythropoiesis in the frog Rana temporaria]. / Sezonnaia dinamika éritropoéza liagushki Rana temporaria.

Studies have been made on the dynamics of erythropoietic activity of the bone marrow in mature female frogs. Evident monocyclic pattern of erythroid blood production was found, its maximum activity being closely related to seasonal changes in physiological reparation of the main bulk of functional systems of frog's organism. The data obtained indicate that the bone marrow is the main site of erythropoiesis in the frog.

[Features of vertebrate brain Na,K-adenosine triphosphatase activation by detergents]. / Osobennosti aktivatsii detergentami Na,K-adenozintrifosfatazy golovnogo mozga pozvonochnykh.

Studies have been made on changes in the activity of Na,K-ATPase in brain homogenates of vertebrates (rat, hen, frog, tortoises) induced by various detergents (sodium deoxycholate, Twin-20, Twin-80, Triton X-100). After application of detergent at optimal concentrations, usually the enzymic activity increased, the increase being dependent on animal species and the brain structure. In crude homogenate of the forebrain, Na,K-ATPase activity was the highest in hen and was altogether absent in frog; detergents practically did not affect the enzymic activity in hen and sharply increased it in frogs. It is suggested that the activating effect of detergents is associated with damage of vesicular membrane structures which are formed during homogenization of the brain tissue, the degree of vesicularization being dependent on fatty acid composition of membrane phospholipids of the brain.