Influence of polar time record on the oxygen transportation function of blood of northerners of various age

According to the theory of functional systems [1; 2], functional system of breath, which unites external respiration, cardiovascular system and the oxygen transportation function, is a very labile structure. It redevelops fast in response to actions of organismic and exogenous factors, providing adequate for organism demands in oxygen balance. Climate and geographical factors of Arctic and North are recognized to be serious irritators of oxygen transportation function of blood, they influence ecology of man as well as management of people in harsh environmental conditions.

When investigating functional systems of a man it is important to take into account that stress shielding on the North are based on age-related changes, and it is difficult to imagine a priori how they correlate with each other during particular age period. Based earlier method of population cross-section when analyzing the function of external respiration and oxygen transportation function of blood [3] let analyze both age and lifetime on the North (Polar life), to emphasize periods of stress shielding, fledging period or interim period, period of relative stabilization and destabilization. The disadvantage of this method appeared to be that it doesn’t answer following questions: Will these periods be developed by northerners, who came to the North when they were 20, 30 or more years old? When yes, will the length of periods be the same? Is it possible to speak about presenilation when reduction of reserved data relatively to temperate data? Some of these questions were answered during correlational study of polar life with respiratory function [4] and blood gas composition of men in different aging groups (20—29, 30—39, 40—49 and 50—

59 years) [5].

Ecological factors of the Arctic and North directly influence the make up of erythron system. Oxygen transportation function is sensitive to low temperatures and other stressors, it is prone to various changes during development of pathological situations. Being the part of functional system of O 2 transportation, changing of this function could reflect its adaptive opportunities for people of the Arctic regions. As an evidence of ecological factors influence are considered to be exertion of erythropoiesis with high activeness of erythropoetin [6], reduction of erythrocyte life expectancy [7; 8; 9]. By that the connection with latitude is evident: the farther to the North, the smaller life expectancy of erythrocytes was, and the intensity of daily erythropoiesis and the average volume of erythrocytes were increasing [8, p. 191; 9, p. 54]. But till today it is not stated whether there is a connection between polar experience and northerners’ transportation function of blood and how it changes in people, who came to the North in different periods of time. The goal of research was to investigate special aspects of blood transportation function by comers of different age groups and polar experience.

Methods

For investigation of blood transportation function we surveyed on a voluntary basis men 20-59 years old in different districts of the Taimyr (Dolgano-Nenets) Autonomous District1. 4 groups were formed according to age. The first group were men aged 20—29 years old (п=75), the second — 30—39 years old (п=90), the third — 40—49 years old (п=47) and the fourth — 5059 years old (п=43). According to length of residence in the North (74о N.) we marked groups with different polar experience (from 1 year, from 1 to 2 years, from 2 to 5 years, from 5 to 10 years, 10 years and more).

Quantity determination of erythrocytes (Er) was conducted in hemoscope M-065. Hematocrit index (Ht) was directly measured in microcentrifuge (Radiometer, Denmark). Haemoglobin contents (Hb) in blood was measured by unified cyanmethemoglobin method with use of acetone cyanohydrin. As calibration solution, a standard fluid of hemiglobincyanide with concentration 59,75 mg% (Reanal, Hungary) was used, which is relevant to International standard solution of hemiglobincyanide. Mean cell haemoglobin concentration was measured in average concentration of this protide in erythrocyte.

Determination of erythrocytes’ diameter was conducted by direct microscopical method with the help of spiral eyepiece micrometer. Blood for determination of erythrocytes’ diameter was taken from median cubital vein into tube with heparine (10 cell/ml) according to recommendations of International Committee for Standardization in Hematology [10]. Indication of average diameter of erythrocytes and variation limits of cellules’ diameter (minimum and maximum) was carried out. In dried blood smears we found the place, where erythrocytes were situated in one stratum and gauged the diameter of 500 cellules. Using the data of average diameter of erythrocytes (DE) we performed computation of average volume of erythrocytes (AvVE), index of sphericity (IS) and thickness of cellule (TC). Investigations were conducted under expedition conditions in spring-summer period.

As an experimental group we used results of investigations of 95 practically healthy men who live in Novosibirsk (55о N) at the age of 22—55 years old.

Statistical analysis of the results was conducted with the use of statistical package CSS. Numeric data were expressed during the work as mean±mean error (M±m). As boundary value of fidelity we used confidence level р<0.05.

Results of investigation

Oxygen transportation function of blood firstly depends on condition of Hb-erythocytes carriers. Residents aged 20—29 years old who have Nordic experience less than 1 year, number of erythrocytes was higher in comparison with the same number in other experimental group (table 1). Further increase of Nordic experience didn’t influence the number of erythrocytes and it ranged from 4,4 to 4,6х1012/l. In the age group of 30-39 years old number of erythrocytes was higher during all the Nordic experience in comparison with other experimental group, which let us speak about erytrocytosis. In the age group 40—49 years old Nordic experience didn’t influence the number of erythrocytes: it corresponded to age norm of mid latitude residents.

By northerners of the age group 20—29 years old who had Nordic experience less than 1 year number of Hb, as well as of erythrocytes, was higher in comparison with other experimental group which speaks about hyperhemoglobinemia (table 1). In the period of residence in the North for 2—10 years it is noted statistically that it is lowering in comparison with the index of the corresponding age group. In the group of the 30—39 years old concentration of Hb didn’t depend on Nordic experience and was the same as the other experimental group. In the age group of 40—49 years old northerners with Nordic experience of 2—5 years concentration of Hb appeared to be mionectic (hypohemoglobinemia), with increase of Nordic experience a tendency to reduction during essential data scatter was determined.

Table 1

Number of erythrocytes and concentration of Hb by Northerners depending on age and Nordic experience

Age, years	Nordic experience, years (n)	Er х1012/l	Hb, g/l
	less than 1 year (19)	4,68 ± 0,11	153,6 ± 3,13
	from 1 to 2 (33)	4,58 ± 0,6	152,0 ± 2,9
	from 2 to 5 (9)	4,43 ± 1,2	136,0 ± 2,42
20 — 29	from 5 to 10 (8)	4,61 ± 0,4	125,1 ± 1,83
	10 and more (6)	4,55 ± 0,8	155,1 ± 3,61
	Experimental group (п=54)	4,41± 0,07	145,9± 2,2
	less than 1 year (12)	5,12 ± 0,33	151,6 ± 6,5
	from 1 to 2 (13)	4,57 ± 0,093	149,3 ± 4,4
	from 2 to 5 (20)	5,16 ± 0,42	135,3 ± 8,6
30 — 39	from 5 to 10 (26)	5,27 ± 0,33	135,8 ± 5,1
	10 and more (19)	5,06 ± 0,41	136,4 ± 5,6
	Experimental group (п=24)	4,09±0,07	146,4± 2,7
	less than 1 year (5)	4,32 ± 0,5	153,7 ± 1,8
	from 2 to 5 (6)	4,36 ± 0,7	143,1 ± 1,72
40 — 49	from 5 to 10 (12)	4,99 ± 0,09	144,8 ± 15,6
	10 and more (24)	4,92 ± 0,07	143,2 ± 8,9
	Experimental group (п=10)	4,39±1,2	152,5± 2,3
	from 2 to 5 (5)		144,1±3,7
	from 5 to 10 (24)	5,09±1,1
50 — 59	10 and more (14)	4,71 ± 0,073
	Experimental group (п=7)	4,22± 0,05	150,3± 4,3

Note: 1- р<0,05, 2- < 0,01, 3- <0,001 — according to current experimental group; within brackets there is a number of participants in the group; Er х1012/l is a number of erythrocytes; Hb — haemoglobin

Results which we got with the help of Hematology Analyzer showed that minimum percentage of Hb (138 g/l) is characteristic for Northerners who lived in the North for 3 years, and maximum (168 g/l) — for 8 years independent from the age group [11].

For indication of Ht-index we used finger-capillary blood (capillary Ht) and median cubital vein venous blood (venous Ht). In group of the 20—29 years old venous Ht was increased inde- pendent from Nordic experience in comparison with data of other experimental group (table 2).

Capillary Ht was also increased except those northerners with Nordic experience 2—5 years.

Table 2

Hematokrit blood index by Notherners

Age, years old	Nordic experience, years (n)	capillary	Ht, % venous
	less than 1 year	52,2 ± 0,83	55,2 ± 0,93 *
	from 1 to 2	52,1 ±0,43	54,6 ± 0,83 *
20 — 29	from 2 to 5	50,4 ± 1,7	55,0 ± 2,11
	from 5 to 10	53,2 ± 1,53	54,8 ± 1,12
	10 and more	52,8 ±0,73	55,6 ± 0,63 *
	less than 1 year	51,5 ±2,0	48,8 ± 4,1
	from 1 to 2	49,2 ± 1,8	53,0 ± 2,3
30—39	from 2 to 5	52,9 ± 1,22	55,4 ± 1,43
	from 5 to 10	51,2 ± 0,82	55,7 ± 0,93 *
	10 and more	52,5 ±1,62	55,8 ± 1,23
	less than 1 year	49,0 ± 0,32	51,2 ± 1,21
40—49	from 2 to 5 from 5 to 10	48,2 ± 2,2 51,3 ± 1,61	53,2 ± 0,83 * 54,7 ± 1,9
	10 and more	53,8 ± 1,82	55,7 ± 1,92
	from 2 to 5	55,2+±1,23	55,6±+1,63
50—59	from 5 to 10	52,6 ± 1,13	56,0 ± 1,53
	10 and more	53,9 ± 1,53	57,0 ± 1,43
Experimental group (п=95)		47,2 ± 0,5	48,1 ± 0,8

Note: 1- р<0,05, 2 - < 0,01, 3- <0,001 — according to experimental group; Hb —hemoglobin; Ht — hematokrit index; * - р<0,05 between capillary and venous Ht;

In the age group of the 30—35 years old increase of index is noted by Northerners with Nordic experience from 2 to 5, from 5 to 10 and 10 and more years, as less than 2 years Nordic experience was the same as other experimental group. In the group 40—49 years old increase of capillary and venous Ht was noticed by Northerners with Nordic experience less than 1 year and 10 years and more. By people who live in the North 2—5 and 5—10 years we noticed increase of either venous or capillary Ht. In the group of the 50-59 years old index was increased independent from Nordic experience.

As a rule, venous Ht-index does not differ from the capillary one [12, p. 275]. In the North in the number of cases venous Ht appeared to be higher, than capillary (table 2). It is noted in the group of Northerners aged 20—29 years old with Nordic experience 1-2 years and 10 years and more. In the group 30—39 years old differences was by Northerners with Nordic experience 5— 10 years, in the group 40—49 years old — with Nordic experience 2-5 years.

Moderate increase of Ht-index could speak for development of symptomatic erytrocytosis, which accompany respiratory embarrassment, particular forms of hemoglobinopathies and hypoxic states. But increase of number of erythrocytes was noticed only in the group 30—39 years old, in group 20—29 years old by Northerners with Nordic experience less than 1 year and in group 50—59 years old with Nordic experience 10 and more years (table 1), while increase of Ht-index was noticed by practically all the groups. In such a way, changes of Ht-index could be connected with morphofunctional features of erythrocytes. The conducted merphometric assessment of erythrocytes of northern comers showed, that Ht index is increased not so much because of absolute increase of erythrocytes, as because of changes in their form and size (tables 3, 4).

• Table 3

Physiological anisocytosis, average diameter and surge of erythrocytes’ diameter of Northern comers depending on age and Nordic experiment

Age, years	Nordic experience years, (n)	PA	ED, mkm
			average	minimum	maximum
	less than 1 year	2,82±0,061	7,47±0,03	6,05±0,14	8,89±0,11
	from 1 to 2	2,77±0,07	7,50±0,01	6,14±0,07	8,93±0,04
20-29	from 2 to 5	2,67±0,16	7,58± 0,02	6,27±0,08	8,95±0,14
	from 5 to 10	2,68±0,17	7,53±0,09	6,32±0,11	9,0±0,17
	10 and more	2,92±0,22	7,52±0,02	6,20±0,23	9,12±0,091
	less than 1 year	2,58±0,16	7,47±0,02	6,21±0,14	8,80±0,08
	from 1 to 2	2,57±0,15	7,49±0,02	6,27±0,15	8,85±0,05
30-39	from 2 to 5	2,40±0,12	7,51±0,03	6,34±0,10	8,74±0,07
	from 5 to 10	2,54±0,07	7,49±0,02	6,23±0,08	8,82±0,04
	10 and more	2,78±0,18	7,43±0,03	6,10±0,12	8,89±0,11
	less than 1 year	2,76±0,22	7,55±0,02	6,50±0,16	9,22±0,151
40-49	from 1 to 2	2,25±0,151	7,55±0,05	6,60±0,151	8,85±0,15
	from 2 to 5	3,0±0,20	7,45±0,05	6,0±0.22	9,0 ±0,15
	from 5 to 10	2,63±0,12	7,49±0,02	6,33±0,09	8,96±0,13

10 and more	2,54±0,09	7,52±0,02	6,32±0,08	8,92±0,07
from 2 to 5	3,35±0,35	7,49±0,05	5,67±0,172	9,02±0,28
50-59            from 5 to 10	2,25±0,30	7,54±0,05	6,45±0,18	8,7±0,17
10 and more	2,55±0,09	7,50±0,02	6,40±0,08	9,05±0,13
Experimental group (п=95)	2,61±0,07	7,51±0,07	6,20±0,06	8,80±0,06

Note: 1- р<0,05, 2-<0,01, — according to experimental group. ФА — physiological anisocytosis; ДЭ — erythrocytes’ diameter

Physiological anisocytosis is characterized with presence of erythrocytes of different size. In the group of Northerners with Polar experience less than 1 year and group of the 40—49 years old with Nordic experience of 1—2 years quantity of anisocytosis differed from the same index of experimental group: it was higher in the group of the 20-29 years old and lower in the group of the 40—49 years old (table 3). An average diameter of erythrocytes of Northerners corresponds to index of experimental group. In the group of the 20—29 years old of Northerners with Nordic experience 10 and more years old were noticed erythrocytes with maximum diameter, which increased this index by experimental group. Erythrocytes with maximum diameter were also noticed in the group of the 40—49 years old but only by Northerners with Polar experience less than 1 year. Differences in minimum diameter were noticed in group of the 40—49 years old by Northerners with Nordic experience 1—2 years (increase) and group of the 50—59 years old by Northerners with Nordic experience 2—5 years (reduction) according to index of experimental group. These data are in keeping with results of scanning electron microscope of Northerners’ erythrocytes [13]. When by Moscovites bulk of erythrocytes is presented by discocytes-normocytes (68%), by Northerners except the population of normocytes (42%) number of microcytes was increased (from 14% in Moscow to 22% in Magadan) and macrocytes (from 18% in Moscow to 36% in Magadan).

Other characteristics of erythrocytes (TE, AvVE and TC) are put into more changes. In age group 20-29 years old with increase of Nordic experience was noticed a tendency to increase of AvVE (form 111,5±2,46 to 116,2±2,82 fl) (table 4). In group of the 30—39 years old AvVE was increased only by Northerners with Nordic experience of less than 1 year, from 1 to 2 and from 2 to 5 years; after 5 years of residence in the North the index corresponded to temperate norm. In age group 40—49 and 50—59 years old maximum indexes of AvVE were by Northerners with Nordic experience 10 years and more.

• Table 4

Average volume, thickness and sphericity erythrocytes index by Northern comers depending on age and Nordic experience

Age, years	Nordic experience, years	AvVE, фfl	TE, mkm	IS
20-29	less than 1 year	111,5±2,463	2,56±0,073	2,95±0,083
	from 1 to 2	113,7±1,63	2,56±0,043	2,9±0,053
	from 2 to 5	113,6±1,723	2,52±0,043	3,02±0,033
	from 5 to 10	115,2 ±2,43	2,50±0,19	3,03±0,112
	10 and more	116,2±2,822	2,54±0,073	3,0±0,093
30-39	less than 1 year	100,2±3,341	2,29±0,13	3,26±0,23
	from 1 to 2	107,5±3,533	2,49±0,39	3,05±0,49
	from 2 to 5	102,3±3,342	2,28±0,07	3,25±0,13
	from 5 to 10	97,2±2,96	2,35±0,081	3,45±0,13
	10 and more	103,7±8,9	2,37±0,24	3,29±0,35
40-49	less than 1 year	113,5±20,5	2,52±0,41	3,05±0,49
	from 5 to 10	102,8±6,0	2,28±0,14	3,3±0,20
	10 and more	109,2±5,02	2,42±0,022	3,1±0,042
50-59	10 and more	114,5±11,11	2,59±0,033	2,89+ 0,181
Experiment group (п=95)		90,6±1,6	2,15±0,02	3,4±0,03

Note: 1р<0,05, 2 < 0,01, 3 <0,001 — according to experiment group; AvVE — average volume of erythrocytes; TE — thickness of erythrocytes; IS — sphericity index

Increase of average volume by unchanging average diameter of erythrocytes suppose reconfiguration of cellules. It is confirmed with such indexes as TE and AvVE. In the group of the 20—29 years old TE is increased in comparison with this index in experiment group. Exceptions were Northerners with Nordic experience of 5—10 years, where it didn’t differ because of vast data spread from the index of experimental group. In group of the 30—39 years old most of Northerners TE corresponded to data of experimental group. Differences are noticed in group of Northerners with Nordic experience of 5—10 years: their erythrocytes were thicker. In the group 20—29 years old AvVE is mionectic in comparison with experimental group (table 4). In the group of the 30—39 years old AvVE corresponded to analogous index of experimental group. In groups of the 40—49 and 50—59 years old it was lower among Northerners after 10 years of residence in the Arctic.

In such a way, results of investigation showed that oxygen transportation function of blood changes according to age of Northerners and length of their residence in these conditions. When in the group of the 20—29 years old by Northerners with Nordic experience of less than 1 year this function is realized by increase of number of erythrocytes and concentration of Hb, after 2 years it is broken because concentration of hemoglobin doesn’t correspond to temperate concentration — it is lower. In the group of the 30—39 years old moderate erythrocytosis is noticed according to experimental group, by that concentration of Hb corresponds to temperate concentration. For the group of the 40—49 years old characteristic was reduction of Hb concentration among Northerners with Nordic experience of 2—5 years, for the group of the 50—59 years old — development of moderate erythrocytosis by Northerners with Nordic experience 10 and more years.

It is important to take into account that obtained results on number of erythrocytes and concentration of hemoglobin among Northerners don’t differ from normal numbers of healthy men (without any connection with latitude residence). Exceptions were Northerners with Nordic experience of 5—10 years from the age group of the 20—29 years old, among whom concentration of Hb was 125,1±1,8 g/l. This value is lower than permissible limits adopted for healthy men [12, p. 270]. Characteristic changes of erythrocytes among Northerners appeared to be increase of average volume of erythrocytes by unchangeable average diameter, which led to increase of erythrocytes’ thickness and reduction of AvVE. Whereas, these changes could testify changes of membranes structure and cytoskeleton of erythrocytes.

It is well-known that respiratory surface of erythrocytes by its average volume by people is about 3—4 thousand m² [14]. Consequently, by increase of AVE we could expect accretion of erythrocytes’ respiratory surface and in such a way — accretion of diffusion area for О 2 , which could essentially speed up diffusion rate per unit time. Apparently, among Northerners aged 30— 39 years old increase of erythrocytes’ number with moderate increase of AvVE could be overviewed as a mechanism of adaptation for need for О 2 increase in Northern conditions. Probably, we could accept presence of this mechanism by healthy newborn child, by whom AvVE is higher than 106 fl, and later in the wake of child’s rising, this index is decreasing.

Computation of such an index as average concentration of hemoglobin in erythrocyte, which reflects saturation efficiency of erythrocyte with hemoglobin, indicates its decrease in each erythrocyte. By that, with increase of Nordic experience in all age groups this reduction became more and more evident. In the group of the 20—29 years old from 29,5% of Northerners with Nordic experience of less than 1 year to 23,5% of Northerners with Nordic experience from 5 to

10 years. In the group of the 40—49 years old from 30,3% of Northerners with Nordic experience 1—2 years up to 25,9% of Northerners with Nordic experience more than 10 years. Men in experimental group this concentration was 30,4±0,72%.

Reduction of average concentration of hemoglobin in erythrocyte is noticed also among the residents of Magadan (26±1%) and middle altitude (30±1%) in comparison with the residents of Moscow (33±1%) [15]. It is worth noticing that results of erythrocytes’ morphometry of Northerners remind of experimental data, which were achieved by guinea pigs in conditions of oxygen deficiency (рО2 = 48 mm Hg, 9000 m of height). Among these animals there were noticed number of reticulocyte, Ht, Hb, but by that average concentration of hemoglobin in erythrocyte declined, thickness of erythrocytes increased in already 72 hours of hypoxic stimulus influence [16]. Decline of average concentration of hemoglobin in erythrocyte speaks for hypochromasia and is overviewed as stigma of iron deficiency. Of wide extension of latent iron deficiency in Northerners’ organism speaks data of bone marrow histochemical research by accidentally died Northerners [9, p. 56].

In such a way, found changes of morphometric characteristics of erythrocytes influence development of suppositions for intravascular derangements and tissue hypoxia. Increased in volume and thickness cellules are amenable for aggregation and damage of microhemorheology more. Increase of Ht index affects negatively on blood velocity, while leading it to decelerating; as a result comfortable conditions are provided for aggregation of erythrocytes in microcirculation vessels and mass conglutination of leucocytes at vascular walls and their further «occlusion», what in turn lead to breakdown of tela supply with oxygen [17]. These reasonings are supported by data achieved during estimate of microcirculation by the method of biological microscopy of bulbar conjunctiva [18]. 50,7% of survey comers there was noticed aggregation of erythrocytes in vessels of eye ground and retinal. More than 1/3 of population were noticed changes of blood velocity, and 46,6% were noticed aneurysms. The conducted by the author correlation analysis created connections of changes in blood velocity in retinal vessels and aggregation of erythrocytes with levels of plasma lipids and Nordic experience.

Break of intravascular microcirculation is also influenced by changes of red blood cell membrane structure. By researches of L.E.Lapin it is shown increase of lisoform concentration against the background of decrease of total phosphotide content, increase of ropiness of erythrocyte inter septum because of congestion of lipid peroxidation products. The last, according to the author’s point of view, leads to possible appearance of protein-lipidic linkings, which leads to decrease of erythrocytes’ deformability. We can suppose that mionectic erythrocytes’ deformability could be to some extend be compensated by decline of average concentration of hemoglobin in erythrocyte, because erythrocytes with high and moderate concentration of hemoglobin in them would have encounter more difficulties during microcirculation vessels circulation. In term, their obstruction through capillary tubes together with other factors create favorable conditions for development of tissue hypoxia.

Together with changes in intravascular microcirculation, connected with founded morpho-functional characteristics of erythrocytes, Northerners experience some stress also with vascular microcirculation. In the Arctic, in the North, capillary permeability is higher with all age groups [20]. But there is a dynamics according to this index, connected with Nordic experience. In the group of the 20— 29 years old Northerners with Nordic experience from 5 to 10 years ductance for protein and filter liquid was mionectic, but after 10 years of residence it again increased. It was noticed earlier, that Northerners of this group have mionectic haemoglobin contents. Together with this, for this group is characteristic increase of lung ventilation [4, p. 19], which provided normal oxygen tension and satiation of capillary blood with oxygen, necessary level of histological metabolism, which speaks for increase of index of venous-capillary difference in oxygen tension with increase of Nordic experience [5, p. 80].

Among Northerners in the group of the 30—39 years old number of erythrocytes was increased, Hb concentration and IS of erythrocytes didn’t stand out from the norm. In this age group capillary permeability for filter liquid and protein by Northerners with Nordic experience from 2 to 5 years was reduced, after 5 years of residence it was constantly increasing. Volume of lung ventilation by them corresponded to temperate norm, after 10 years of residence in the North it was supported by means of increase of breathing rhythm. In this group it was noticed connection with Nordic experience not only with venous-capillary difference in oxygen tension, but also capillary-venous difference in oxygen, what reflects connection of dynamics of tissular metabolism intensity with length of residence in the North. In the group of the 40—49 years morphometric characteristics of erythrocytes after 10 years of residence in the North were different from temperate latitude. Lung ventilation was supported by increase of breathing capacity, after 10 years of residence breath acceleration acceded to this mechanism. Tendency to increase of venous-capillary difference in oxygen tension and capillary-venous difference in oxygen was determined by the well-known phenomenon of shift of energetic metabolism from «carbohydrate» type into «fat».

Educed shift of рН aside to acid intoxication (metabolic or respiratory according to Nordic experience) [5, p. 79] supposes change of affinity of Hb to О2. It could be increased by means of synthesis non relevant for adults of fetal Hb and increase of 2,3-diphosphoglycerate in erythrocytes. But increase of fetal Hb was noticed by Northerners with small Nordic experience or by in- fluence of polar cold by unadapted to low temperatures people [21]. Contrary to the expectations concentration of 2,3-diphosphoglycerate in erythrocytes, measured among the residents of Magadan, didn’t exceed the physiological norm [8, p. 212].

In such a way, achieved results speak of consolidation of role of oxygen transportation function of erythrocytes by Northerners in providing of transportation of oxygen as part of functional breath system. Tension of oxygen transportation function of blood is accompanied by displacement of function of external respiration, transcapillary and gas exchange. In each age group relations between particular compartments of functional breathing system is determined by Nordic experience of Northerners.

Conclusion

Thematic justification of oxygen transportation function of blood in the Arctic, in the North is connected with investigation of mechanisms of northern tissue hypoxia development. Realization of this function is provided by erythrocytes, which are considered to be hemoglobin carriers. In the turn, hemoglobin provides transportation of oxygen and carbon dioxide. Results of erythrocytes’ morphofunctional characteristics analysis of Northerners of different ages depending on Nordic experience let us view different adaptive potential by young and middle-aged people. In the group of the 20—29 years old, Northerners with small Nordic experience increase oxygen capacity of blood by means of moderate erythrocytosis and hyperhemoglobinemia. After two years of residence in the North there is lack of erythrocytosis, haemoglobin contents lowers; after 5 years it is lower than the lower limit of physiological norm. But after 10 years of residence in the North hyperhemoglobinemia develops. In the group of the 30—39 years old among all Northerners, no matter how long they live in the North, erythrocytosis is noticed, haemoglobin contents corresponds to temperate norms. But with increase of Nordic experience a tendency to its decline is noticed. In the group of the 40—49 years old among Northerners after 2 years of residence in the North hyperhemoglobinemia is noticed according to temperate norm. Educed changes of oxygen transportation function of erythrocytes by Northerners depending on Nordic experience are compensated by alteration of external respiration, transcapillary and gas exchanges. Such an interaction between erythrocytes, respiratory system and vessels is considered to be an evidence of mobilization of functional respiratory system and their functioning on a new level, necessary for adequate providing of cells and tissues with oxygen in Arctic conditions. Insufficient interaction or disagreement between particular compartments of breathing functional system create conditions for development of the northern tissue hypoxia, which negatively influences the ecology of a man.