Aim. The article deals with evaluating the changes in minute volume of blood circulation and the features of regional hemodynamics in somatic and visceral organs during intensive muscular activity. Materials and methods. Studies were conducted on outbred laboratory dogs (n = 16). At rest and at maximum physical exertion (running on a treadmill to failure), oxygen consumption (VO2), blood gas composition, the minute volume of respiration (VE) and blood circulation (Q) (according to Fick) were determined. The volumetric blood flow velocity in skeletal muscles and visceral organs (qt) was determined by introducing iodine-131-labeled microspheres into the heart cavity. Results. At maximum physical exertion, VO2 significantly increases by 11.7 times, Q – by 5.3 times. The volumetric blood flow velocity significantly (P ≤ 0.001) increases in locomotor (6.2–7.5 times) and respiratory (6.5–8.0 times) muscles. In postural muscles, blood flow does not change. In the myocardium, blood flow increases by 4.5 times and corresponds to changes in cardiac performance. In the adrenal gland, blood flow increases by 1.6 times (p ≤ 0.001), in the thyroid gland, it remains unchanged. In the kidney, blood flow decreases by 21.5%, in the liver by 23.0%, with an increase in the arterial fraction by 56.3% of organs. In organs of the splanchnic region (spleen, organs of the gastrointestinal tract), the volumetric blood flow velocity decreases by 44.9% (P ≤ 0.001). Conclusion. During extreme physical exertion, most of the cardiac output is distributed into the locomotor, respiratory muscles and organs involved in muscle activity, while reducing the volumetric blood flow in the visceral organs. It is postulated that against the background of high oxygen demand and arterial hypoxemia in the somatic and visceral organs, there are competitive relationships for blood flow and the prerequisites for the development of total tissue hypoxia.
The nature of nutrition modifies the metabolism of substances and ensures either normal functioning or contributes to metabolic disorders and the development of pathologies. A study was made of the effect of different feeding diets (lipid, carbohydrate and protein) on the blood biochemical profile of adult sexually mature rats. The work was performed on 28 white laboratory male rats weighing 180–250 g, which were 4 groups: the first (1) group (n=7) was fed exclusively with lipids (fat tail fat), the second (2, n=7) — carbohydrates (sugar), the third (3, n=7) — proteins, and the fourth (4, n=7) — standard food. The levels of glucose, cholesterol, total protein and albumin were determined by the colorimetric method. It was revealed that when taking lipid food in the blood, levels of cholesterol, glucose, total protein and albumin increased; when consuming carbohydrate feed — the content of glucose and lipids; when consuming a protein diet — total protein, albumin and lipids. The concentration of cholesterol increased with the use of all types of diet, especially significantly with lipid. Thus, glucose concentration increased with carbohydrate and lipid diets; total protein — with protein; glucose equally — with lipid and carbohydrate. The highest concentration of albumin is observed with a lipid diet, the lowest — with a carbohydrate.
Mountains occupy about 24 % of the land surface. There are significant natural resources here, the development of which is associated with an increased traumatic risk. Craniocerebral injuries in the mountains are very frequent, and microvascular dysfunction, as under ordinary conditions, is a key element in the chain of events in the central nervous system. However, there are very few data on vascular plexuses and brain microcirculation in craniocerebral injury that occurs in the mountains. The aim of the study is to reveal the patterns in remodeling of vascular plexuse and main elements of brain microcirculation in craniocerebral injury that occurs in the mountains. Materials and Methods. The study enrolled 46 white outbred male laboratory rats (210–270 g) with simulated low-mountain (760 m above sea level, Bishkek) and high- mountains (Too Ashuu mountain pass, 3200 m above sea level) traumatic brain injury. The authors used the weight-drop method (Y. Tang technique) to reproduce the traumatic brain injury. After reproduction of the trauma in high altitudes, the animals were transported to low altitudes and on the 3rd day the rats were sacrificed with chloroform overdose. The authors studied microcirculation using a microscopic method with black ink intravascular injection. Olympus Bx40 microscope (Japan) was used for this purpose. At the same time, serial microphotography with simultaneous recording of the results was carried out using a digital camera connected to a computer. The morphometry of the vascular plexuse brain components was carried out with Top View application used for measuring microscopic objects. SPSS 16.0 software was used to process statistical data. Results. Craniocerebral injury that occurs in high mountains causes the narrowing of the capillary lumen by 52 % (p<0.001). In comparison with low mountains, the capillary lumen in high mountains decreases by 42 % (p<0.001). Venous plethora is observed. In vascular plexuses in the highlands, remodeling of the cellular component is recorded: ependymocyte volume increases by 23 % (p<0.05), nucleus volume – by 30 % (p<0.001), and cytoplasm volume – by 22 % (p<0.05). Conclusion. Craniocerebral injury leads to the development of cytotoxic edema in the vascular plexus stroma and to remodeling of brain microcirculation, which is the pathogenetic basis for hypertension and increased intracranial pressure. In the highlands, these phenomena are more pronounced and are accompanied by blood flow centralization. Keywords: microcirculation, vascular plexuses, brain, craniocerebral injury, highlands. Горы занимают около 24 % территории суши. Здесь располагаются значительные природные ресурсы, освоение которых сопряжено с повышенным риском травматизма. Черепно-мозговая травма на горных высотах – частое явление, а микрососудистая дисфункция, как и в обычных условиях обитания человека, является ключевым звеном в цепи событий, развертывающихся в центральной нервной системе. Однако данных о состоянии сосудистых сплетений и микроциркуляции головного мозга при черепно-мозговой травме, возникшей в высокогорье, крайне мало. Цель исследования – выявить закономерности ремоделирования сосудистых сплетений и основных звеньев микроциркуляции головного мозга при черепно-мозговой травме, возникшей в условиях высокогорья. Материалы и методы. Объектом исследования послужили 46 белых беспородных лабораторных крыс-самцов весом 210–270 г, которым моделировалась черепно-мозговая травма в условиях низкогорья (высота 760 м над уровнем моря, г. Бишкек) и высокогорья (перевал Туя-Ашу, 3200 м над уровнем моря). Для воспроизведения черепно-мозговой травмы использовалась ударная модель weight drop method по Y. Tang. После воспроизведения травмы в условиях высокогорья животных транспортировали в условия низкогорья и на 3-и сут выводили из эксперимента путем передозировки хлороформа. Микроциркуляция изучалась микроскопическим методом с применением внутрисосудистого инъецирования раствором черной туши. Препараты изучались под микроскопом Olympus Bx40 (Япония). Параллельно проводилось серийное микрофотографирование с помощью цифрового фотоаппарата, подключенного к компьютеру, с одновременным протоколированием результатов. Морфометрия компонентов сосудистых сплетений головного мозга осуществлялась с помощью приложения для измерения микроскопических объектов Top View. Статистическая обработка данных проводилась в программе SPSS 16.0. Результаты. Черепно-мозговая травма, возникшая в условиях высокогорья, приводит к сужению просвета капилляров на 52 % (p<0,001), при этом в сравнении с низкогорьем просвет капилляров в высокогорье уменьшается на 42 % (p<0,001). Отмечаются явления венозного полнокровия. Со стороны сосудистых сплетений в высокогорье регистрируется ремоделирование клеточного компонента: объем эпендимоцитов возрастает на 23 % (p<0,05), объем ядра – на 30 % (p<0,001), объем цитоплазмы – на 22 % (p<0,05). Выводы. Черепно-мозговая травма привела к развитию цитотоксического отека стромы сосудистого сплетения и ремоделированию системы микроциркуляции головного мозга, что является патогенетической основой гипертензии и повышения внутричерепного давления. В высокогорье эти явления выражены в большей степени и сопровождаются признаками централизации кровообращения. Ключевые слова: микроциркуляция, сосудистые сплетения, головной мозг, черепно-мозговая травма, высокогорье.
Human activity is associated with the risk of injury. The rate of cases of traumatic brain injury (TBI) in high-altitude conditions is high. It should be assumed that exogenous hypoxia will have a significant impact on the development of the clinical consequences of TBI. However, information about the behavior of animals on the background of TBI in the highlands is scarce. The search for means of correcting brain injuries remains an urgent issue. To date, glibenclamide has been proposed for this purpose, but its effect in the highlands has not been studied. Objective: to evaluate the effect of glibenclamide on the behavioral activity of animals with TBI in the highlands. The object of the study is 82 white male rats weighing 250–310 g. The low-mountain series of the experiment was carried out at an altitude of 760 m above sea level (Bishkek). The high-altitude series was modeled on the Tuya-Ashu pass — 3200 m above sea level (Kyrgyzstan). TBI was reproduced according to the method of Y. Tang (1997). Correction with glibenclamide at a dose of 0.1 mg/kg per os. Behavioral activity was evaluated using the Open Field method, and muscle strength was evaluated using the S. V. Speransky method on the 3rd day of the experiment. Statistical processing of the obtained data was carried out in the SPSS 16.0 program. TBI in the low mountains resulted in a decrease in locomotor activity by 67% (P<0.001), and efficiency — by 43% (P<0.001). In the group of rats with TBI in the highlands, compared with the data of healthy animals that visited the same altitude, locomotor activity decreased by 44% (P<0.001), racks — by 60% (P<0.001), minks — by 76% (P< 0.01), grooming — by 55% (P<0.01), the number of boluses of defecation increases by 37% (P<0.05). Correction of TBI with glibenclamide in the highlands led to an increase in locomotion by 2 times (P<0.001), standing — by 2.3 times, peering into minks — by 4 times (P<0.01), working capacity — by 2.04 times (P<0.001). The level of defecation decreased by 70% (P<0.001). Violations of the behavior of rats in the highlands with TBI without the use of glibenclamide are more pronounced than in experiments in the foothills. Correction of TBI that occurred in the highlands demonstrates a positive neurotropic effect of glibenclamide.
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