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1732. The role of nitric oxide in the maintenance of vasoactive balance
- Creator:
- Oľga Pecháňová and Fedor Šimko
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, oxid dusnatý, endoteliální dysfunkce, hypertenze, nitric oxide, endothelial dysfunction, hypertension, angiotensin II, endothelins, reactive oxygen species, 14, and 612
- Language:
- English
- Description:
- Endothelial dysfunction may be considered as the interstage between risk factors and cardiovascular pathology. An imbalance between the production of vasorelaxing and vasoconstricting factors plays a decisive role in the development of hypertension, atherosclerosis and target organ damage. Except vasorelaxing and antiproliferative properties per se, nitric oxide participates in antagonizing vasoconstrictive and growth promoting effects of angiotensin II, endothelins and reactive oxygen species. Angiotensin II is a potent activator of NAD(P)H oxidase contributing to the production of reactive oxygen species. Numerous signaling pathways activated in response to angiotensin II and endothelin-1 are mediated through the increased level of oxidative stress, which seems to be in casual relation to a number of cardiovascular disturbances including hypertension. With respect to the oxidative stress, the NO molecule seems to be of ambivalent nature. On the one hand, NO is able to reduce generation of reactive oxygen species by inhibiting association of NAD(P)H oxidase subunits. On the other hand, when excessively produced, NO reacts with superoxides resulting in the formation of peroxynitrite, which is a free radical deteriorating endothelial function. The balance between vasorelaxing and vasoconstricting substances appears to be the principal issue for the physiological functioning of the vascular bed., O. Pecháňová, F. Šimko., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1733. The role of non-aromatizable testosterone metabolite in metabolic pathways
- Creator:
- Michaela Dušková and Pospíšilová, H.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, ateroskleróza, testosteron, atherosclerosis, testosterone, non-aromatizable androgen, adipose tissue, metabolic syndrome, 14, and 612
- Language:
- English
- Description:
- Dihydrotestosterone (DHT) originates via irreversible reduction of testosterone by catalytic activity of 5α-reductase enzyme and it is demonstratively the most effective androgen. Androgens influence adipose tissue in men either directly by stimulation of the androgen receptor or indirectly, after aromatization, by acting at the estrogen receptor. DHT as a non-aromatizable androgen could be responsible for a male type fat distribution. The theory of non-aromatizable androgens as a potential cause of a male type obesity development has been studied intensively. However, physiological levels of DHT inhibit growth of mature adipocytes. In animal models, substitution of DHT in males after gonadectomy has a positive effect on body composition as a testosterone therapy. Thus, DHT within physiological range positively influences body composition. However, there are pathological conditions with an abundance of DHT, e.g. androgenic alopecia and benign prostatic hyperplasia. These diseases are considered as ri sk factors for development of metabolic syndrome or atherosclerosis. In obese people, DHT metabolism in adipose tissue is altered. Local abundance of non- aromatizable androgen has a nega tive effect on adipose tissue and it could be involved in pathogenesis of metabolic and cardiovascular diseases. Increased DHT levels, compared to physiological levels, have negati ve effect on development of cardiovascular diseases. Difference between the effect of physiological and increased level brings about certain paradox., M. Dušková, H. Pospíšilová., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1734. The role of protease-activated receptor type 2 in nociceptive signaling and pain
- Creator:
- Mrozkova, P., Palecek, J., and Spicarova, D.
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, bolest, mícha, pain, spinal cord, protease-activated receptor (PAR2), signaling pathways, nociception, 14, and 612
- Language:
- English
- Description:
- Protease-activated receptors (PARs) belong to the G-proteincoupled receptor family, that are expressed in many body tissues especially in different epithelial cells, mast cells and also in neurons and astrocytes. PARs play different physiological roles according to the location of their expression. Increased evidence supports the importance of PARs activation during nociceptive signaling and in the development of chronic pain states. This short review focuses on the role of PAR2 receptors in nociceptive transmission with the emphasis on the modulation at the spinal cord level. PAR2 are cleaved and subsequently activated by endogenous proteases such as tryptase and trypsin. In vivo, peripheral and intrathecal administration of PAR2 agonists induces thermal and mechanical hypersensitivity that is thought to be mediated by PAR2-induced release of pronociceptive neuropeptides and modulation of different receptors. PAR2 activation leads also to sensitization of transient receptor potential channels (TRP) that are crucial for nociceptive signaling and modulation. PAR2 receptors may play an important modulatory role in the development and maintenance of different pathological pain states and could represent a potential target for new analgesic treatments., P. Mrozkova, J. Palecek, D. Spicarova., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1735. The role of red blood cell deformability and Na, K-ATPase function in selected risk factors of cardiovascular diseases in humans: focus of hypertension, diabetes mellitus and hypercholesterolemia
- Creator:
- Radosinska, J. and Vrbjar, N.
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, erytrocyty, erythrocytes, erythrocyte deformability, Na, K-ATPase, cardiovascular risk factors, 14, and 612
- Language:
- English
- Description:
- Deformability of red blood cells (RBC) is the ability of RBC to change their shape in order to pass through narrow capillaries in circulation. Deterioration in deformability of RBC contributes to alterations in microcirculatory blood flow and delivery of oxygen to tissues. Several factors are responsible for maintenance of RBC deformability. One of them is the Na,K-ATPase known as crucial enzyme in maintenance of intracellular ionic homeostasis affecting thus regulation of cellular volume and consequently RBC deformability. Decreased deformability of RBC has been found to be the marker of adverse outcomes in cardiovascular diseases (CVD) and the presence of cardiovascular risk factors influences rheological properties of the blood. This review summarizes knowledge concerning the RBC deformability in connection with selected risk factors of CVD, including hypertension, hyperlipidemia, and diabetes mellitus, based exclusively on papers from human studies. We attempted to provide an update on important issues regarding the role of Na,K-ATPase in RBC deformability. In patients suffering from hypertension as well as diabetes mellitus the Na,K-ATPase appears to be responsible for the changes leading to alterations in RBC deformability. The triggering factor for changes of RBC deformability during hypercholesterolemia seems to be the increased content of cholesterol in erythrocyte membranes., J. Radosinska, N. Vrbjar., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1736. The role of renin-angiotensin system in prothrombotic state in essential hypertension
- Creator:
- Anna Remková and Milan Remko
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, endotel, hypertenze, endothelium, hypertension, platelet, coagulation, fibrionolysis, 14, and 612
- Language:
- English
- Description:
- Rheological, haemostatic, endothelial and platelet abnormalities appear to play a role in the thrombotic complications of hypertension. This prothrombotic/hypercoagulable state in hypertension may contribute to the increased risk and severity of target organ damage. It can be induced by the activated reninangiotensin system (RAS), with abnormalities in endothelial and platelet function, coagulation and fibrinolysis. Treatment of uncomplicated essential hypertension by RAS targeting antihypertensive therapy could result in a reversal of prothrombotic abnormalities, contributing to a reduction of thrombosis-related complications. Since angiotensin converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) have two distinct mechanisms of RAS interruption, it is hypothesized that each therapy might have different impact on the prothrombotic state in hypertensive patients. Some studies demonstrate a beneficial effect of both ACE inhibitors and ARBs on prothrombotic state, in addition to their efficacy to normalize elevated blood pressure. The potentially antithrombotic effect of the RAS inhibiting agents may in turn support the preservation of cardiovascular function. Available data may offer an additional explanation for the efficacy of the RAS targeting agents in the prevention of cardiovascular events in patients with atherosclerotic vascular disease., A. Remková, M. Remko., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1737. The role of smooth muscle cells in vessel wall pathophysiology and reconstruction using bioactive synthetic polymers
- Creator:
- Martin Pařízek, Novotná, K., and Lucie Bačáková
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, tkáňové inženýrství, nanostruktury, tissue engineering, nanostructures, bioartificial vascular grafts, polymer irradiation, dynamic bioreactor, 14, and 612
- Language:
- English
- Description:
- This review summarizes recent trends in the construction of bioartificial vascular replacements, i.e. hybrid grafts containing synthetic polymeric scaffolds and cells. In these advanced replacements, vascular smooth muscle cells (VSMC) should be considered as a physiological component, although it is known that activation of the migration and proliferation of VSMC plays an important role in the onset and development of vascular diseases, and also in re stenosis of currently used vascular grafts. Therefore, in novel bioartificial vascular grafts, VSMCs should be kept in quiescent mature contractile phenotype. This can be achieved by (1) appropriate physical and chemical properties of the material, such as its chemical composition, polarity, wettability, surface roughness and topography, electrical charge and conductivity, functionalization with biomolecules and mechanical properties, (2) appropriate cell culture conditions, such as composition of cell culture media and dynamic load, namely cyclic strain, and (3) the presence of a confluent, mature, semipermeable, non-thrombogenic and non-immunogenic endothelial cell (EC) barrier, covering the luminal surface of the graft and separating the VSMCs from the blood. Both VSMCs and ECs can also be differentiated from stem and progenitor cells of various sources. In the case of degradable scaffolds, the material will gradually be removed by the cells and will be replaced by their own new extracellular matrix. Thus, the material component in advanced blood vessel substitute s acts as a temporary scaffold that promotes regeneration of the damaged vascular tissue., M. Pařízek, K. Novotná, L. Bačáková., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1738. The role of spinal cord vanilloid (TRPV1) receptors in pain modulation
- Creator:
- Špicarová, Diana. and Jiří Paleček
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, neurofyziologie, morfologie (biologie), mícha, neurophysiology, morphology (biology), spinal cord, hyperalgesia, capsaicin, vanilloid 1 receptors (TRPV1), 14, and 612
- Language:
- English
- Description:
- Transient receptor potential vanilloid 1 (TRPV1) receptor is a nonselective cation channel activated by capsaicin, a pungent substance from chili peppers. It is considered to act as an integrator of various physical and chemical nociceptive stimuli, as it can be gated by noxious heat (>43ºC), low pH (protons) and also by recently described endogenous lipids. The structure and function of TRPV1 receptors was vigorously studied, especially since its cloning in 1997. However, most of the research was pointed towards the role of TRPV1 receptors in the peripheral tissues. Mounting evidence now suggests that TRPV1 receptors on the central branches of dorsal root ganglion neurons in the spinal cord may play an important role in modulation of pain and nociceptive transmission. The aim of this short review was to summarize the knowledge about TRPV1 receptors in the spinal cord dorsal horn, preferentially from morphological and electrophysiological studies on spinal cord slices and from in vivo experiments., D. Špicarová, J. Paleček., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1739. The role of steroid hormones in the development of intrahepatic cholestasis of pregnancy
- Creator:
- Antonín Pařízek, Michaela Dušková, Libor Vítek, Šrámková, M., Hill, M., Adamcová, K., Šimják, P., Černý, A., Kordová, Z., Vráblíková, H., Boudová, B., Michal Koucký, Karin Malíčková, and Luboslav Stárka
- Format:
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, cholestáza, selen, těhotenství, cholestasis, selenium, pregnancy, allopregnanolone - epiallopregnanolone, 17β-estradiol, farnesoid, receptor, leaky gut in pregnancy, 14, and 612
- Language:
- English
- Description:
- Intrahepatic cholestasis of pregnancy (ICP) is a disorder of liver function, commonly occurring in the third trimester but sometimes also as soon as the end of the second trimester of pregnancy. Symptoms of this disorder include pruritus, plus abnormal values of bile acids and hepatic transaminases. After birth, symptoms disappear and liver function returns to normal. Though ICP is relatively non-complicated and often symptomatically mild from the point-of-view of the mother, it presents a serious risk to the fetus, making this disease the subject of great interest. The etiology and pathogenesis of ICP is multifactorial and as yet not fully elucidated. Hormonal factors likely play a significant role, along with genetic as well as exogenous factors. Here we summarize the knowledge of changes in steroid hormones and their role in the development of intrahepatic cholestasis of pregnancy. In addition, we consider the role of exogenous factors as possible triggers of steroid hormone changes, the relationship between metabolic steroids and bile acids, as well as the combination of these factors in the development of ICP in predisposed pregnant women., A. Pařízek, M. Dušková, L. Vítek, M. Šrámková, M. Hill, K. Adamcová, P. Šimják, A. Černý, Z. Kordová, H. Vráblíková, B. Boudová, M. Koucký, K. Malíčková, L. Stárka., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1740. The role of stress hormones in dental management behavior problems
- Creator:
- Michaela Dušková, Vašáková, J., Jana Dušková, Jana Kaiferová, Zdeněk Broukal, and Luboslav Stárka
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fobie, strach, úzkost, kortizol, phobias, fear, anxiety, cortisol, dental treatment, adrenals, catecholamines, 14, and 612
- Language:
- English
- Description:
- Dental management behavior problems are thought to be both multifactorial and multidimensional, consisting of physiological, behavioral and cognitive components. The stress response to pain or even the anticipation of distress initiates activation of the hypothalamic-pituitary-adrenal axis and causes an increase of cortisol and catecholamines. The literature on the role of hormones in dental management behavior problems comprises about one hundred papers, which have mainly been focused on this activation of the HPA axis in various situations in dental care. They have generally used salivary cortisol as a marker of the activity of the HPA axis, sometimes combined with salivary alpha amylase. Here we summarize the literature data on the role of stress hormones in dental management behavior problems., M. Dušková, J. Vašáková, J. Dušková, J. Kaiferová, Z. Broukal, L. Stárka., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public