Wyniki wyszukiwania - Biblioteka Nauki

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The role of external Ca2plus in the action of Ca2plus-channel agonists and antagonists on isolated human thoracic arteries

100%

Garaliene V. , Barsys V. , Giedraitis S. , Benetis R. , Krauze A.

Journal of Physiology and Pharmacology

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2014

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tom 65

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nr 1

2

ФУНКЦІОНАЛЬНИЙ СТАН КАРДІОРЕСПІРАТОРНОЇ СИСТЕМИ СТУДЕНТІВ, ЩО СПЕЦІАЛІЗУЮТЬСЯ В БІАТЛОНІ В БАЗАЛЬНИХ УМОВАХ

86%

Приймак С.

Педагогічні науки: теорія, історія, інноваційні технології

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2017

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nr 9(73)

108-120

EN

In modern theory and practice of physical education and sports, sports pedagogy, one of the main areas of training future specialists is to ensure proper management of sports and pedagogical improvement on the basis of objectivization of knowledge about the structure of activity and functional state of the organism. The purpose of the article was to study the functional state of the cardiovascular system of students specializing in biathlon. Methods.Analysis, synthesis, comparison, classification, specification, synthesis of scientific sources on the research problem; study of pedagogical experience, normative legal acts to clarify the essence of the basic concepts of research; pulsometry, tonometry, photoplethysmography, spirography, methods of mathematical statistics. Results. Biathlon students with a relative equilibrium of regulation (eutonium) of cardiovascular activity have a certain tendency to para-, sympathetic dominance, depending on gender. The patterns of the relationship between HRV and pulse wave parameters in women have a lower level of probable significance (p≤0.05), which indicates a relatively lower influence of the para-, sympathetic components of regulation of the tone of peripheral vessels. Conclusion.The revealed patterns indicate the dominance of men in the aerobic component of the functional provision of activities, unlike women, in which this tendency is manifested to a lesser extent, which, in turn, determines the propensity to a greater humoral (ergotropic) and sympathetic regulation of cardiovascular activity. Further research is aimed at determining the functional state of cardioghemodynamics and the autonomic regulation of cardiac rhythm of students specializing in biathlon, depending on the personality’s temporal peculiarities. Taking into account the above-mentioned regularities of functional support of the activity will allow teachers, trainers, and specialists in physical culture to optimize the process of sports and pedagogical training of students in biathlon, depending on gender.

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Involvement of central and peripheral histamine H3 receptors in the control of the vascular tone and oxygen uptake in the mesenteric circulation of the rat

86%

Obuchowicz R. , Pawlik M. W. , Brzozowski T. , Konturek S. J. , Pawlik W. W.

Journal of Physiology and Pharmacology

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2004

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tom 55

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nr 1,2

EN

Data concerning cardiovascular effects of peripherally and centrally located histamine H3 receptor stimulation are contradictory, and despite excessive studies their role in the control of the cardiovascular function have not been cleared yet. Effect of histamine H3 receptors activation have been attributed to modulation of sympathetic system activity but exact role of peripherally and centrally located histamine H3 receptors stimulation in the modulation of vascular tone of the mesentery and intestinal metabolism remains unexplored. Aim of the present study was to evaluate the role of centrally and peripherally located histamine H3 receptors in the modulation of vascular tone of the mesentery and metabolic activity of intestinal tissue. In anesthetized rats total mesenteric blood flow (MBF), mucosal intestinal blood flow (LDBF), intestinal oxygen uptake (VO2) and arterial pressure (AP) were determined. Intestinal arterial conductance (C) was also calculated. Administration of the selective histamine H3 receptor agonist imetit (10 µmol/kg i.a) evoked marked changes in hemodynamic and metabolic parameters; MBF, LDBF, C and VO2 were significantly increased, whereas AP was significantly decreased. Pretreatment with histamine H3 receptor antagonist clobenpropit (4 µmol/kg i.a.) abolished imetit-induced circulatory and oxygen uptake responses. Clobenpropit (4 µmol/kg i.a.) alone failed to affect the MBF, LDBF, AP, C and VO2 values. Central administration of imetit (0.1 µmol i.c.v.) markedly increased AP and decreased MBF, LDBF, C and VO2. Pretreatment with histamine H3 receptor antagonist clobenpropit (0,4 µmol i.c.v.) diminished circulatory and metabolic responses to centrally injected imetit. Central histamine H3 receptors blockade by clobenpropit evoked no significant changes in the mesenteric arterial and mucosal microcirculatory blood flow, intestinal metabolism and mean arterial pressure. We conclude that, peripheral histamine H3 receptors when stimulated decreases vasoconstrictory tone of the mesenteric artery and precapillary structures and evokes increase of intestinal oxygen uptake. This might be in part due to inhibition of sympathetic postganglionic fibers vasopressor activity. Central histamine H3 receptor stimulation activates vasoconstrictory sympathetic adrenergic system with possible involvement of other, presumably non-histaminergic receptors system. At basal conditions neither central nor peripheral histamine H3 receptors are involved in the control of mesenteric macro - and microcirculation and intestinal oxygen consumption.

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Abrogation of mitochondrial transcription in smooth muscle cells impairs smooth muscle contractility and vascular tone

72%

Jawien J. , Bian Z. , Sheikine Y. , Olofsson P. S. , Pang Y. , Edholm T. , Dou Y. , Metzger D. , Hellstrom P. M. , Feil R. , Hansson G. K.

Journal of Physiology and Pharmacology

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2008

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tom 59

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nr 2

EN

Background: Smooth muscle cells (SMC) constitute the major contractile cell population of blood vessels and inner organs. SMC contraction depends on energy provided by adenosine triphosphate (ATP) catabolism, which can be generated through oxidative phosphorylation in mitochondria or by anaerobic glycolysis. Mitochondrial activity may also modulate smooth muscle tone by biotransformation of vasoactive mediators. Here, we study the role of mitochondrial DNA gene expression for vascular function in vivo. Methods: Since loss of functional mitochondria in SMC may not be compatible with normal development, we generated mice with inducible SMC-specific abrogation of the mitochondrial transcription factor A (Tfam). Deletion of this gene leads to dysfunctional mitochondria and prevents aerobic ATP production in affected cells. Results: Invasive blood pressure monitoring in live animals demonstrated that SMC specific Tfam deletion results in lower blood pressure and a defective blood-pressure response to stress, changes that were not compensated by increased heart rate. The contractility to agonists was reduced in arterial and gastric fundus strips from Tfam-deficient mice. Endothelium-dependent relaxation of arterial strips in response to ACh was also blunted. Conclusion: Our data show that mitochondrial function is needed for normal gastric contraction, vascular tone, and maintenance of normal blood pressure.

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