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1242. Pheochromocytoma and markers of oxidative stress
- Creator:
- Turková, H., Ondřej Petrák, Jan Škrha, Jiří Widimský, and Tomáš Zelinka
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, pheochromocytoma, catecholamines, oxidative stress, 14, and 612
- Language:
- English
- Description:
- High levels of catecholamines in pheochromocytoma (PHEO) are associated with risk of cardiovascular complications. In this study, we looked for potential differences in markers of oxidative stress – vitamin C, superoxide dismutase (SOD) and malondialdehyde (MDA) in PHEO before and after the operation. We studied 18 subjects with PHEO who were examined before and approximately one year after the successful tumor removal (free of disease). All subjects had elevated urinary epinephrine and/or norepinephrine levels before the operation. Vitamin C levels increased significantly after the operation from 61±27 to 77±20 μmol/l (P=0.02), and MDA decreased significantly after the tumor removal from 2.6±0.4 to 2.0±0.6 μmol/l (P=0.01). However, no changes were found in SOD activity before and after the operation. In conclusion, increased catecholamine production in PHEO is accompanied by decreased levels of vitamin C and increased levels of MDA which may indicate the activation of oxidative stress in PHEO. Successful operation was associated with lowering of oxidative stress by using both biomarkers. On the contrary, no changes in SOD activity before and after the tumor removal were noted., H. Turková, ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1243. Phosphodiesterases inhibition enhances the effect of glucagon on cardiac automaticity in the isolated right ventricle of the rat
- Creator:
- Gonzalez-Muñoz, C. and Hernández, J.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, glukagon, glucagon, cyclic nucleotide phosphodiesterases (PDE), cardiac automaticity, isoproterenol, 14, and 612
- Language:
- English
- Description:
- We evaluated the effect of glucagon on cardiac automaticity as well as the possible role of cyclic nucleotide phosphodiesterases (PDE) in regulating this effect. Concentration response curves for glucagon in the absence and in th e presence of the non-selective PDE inhibitor IBMX were performed in the isolated right ventricle of the rat. We found that glucagon produces only a minor increase of ventricular automa ticity (11.0±4.1, n=5) when compared to the full agonist of β-adrenoceptor isoproterenol (182.2±25.3, n=7). However, IBMX enhances the maximal efficacy of glucagon on cardiac automaticity (11.0±4.1, in the absence and 45.3±3.2 in the presence of IBMX, n=5, P<0.05). These results indicate that PDE blunts proarrhythmic effects of glucagon in rat myocardium., C. Gonzalez-Muñoz, J. Hernández., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1244. Phospholemman does not participate in forskolin-induced swine carotid artery relaxation
- Creator:
- Meeks, M. K., Han, S., Tucker, Amy L., and Rembold, Christopher M.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, kardiovaskulární fyziologie, hladké svaly, bílkoviny, cardiovascular physiology, smooth muscles, proteins, cyclic AMP (adenosine monophosphate), FXYD protein, HSP20, myosin light chain, vascular smooth muscle, 14, and 612
- Language:
- English
- Description:
- Phosphorylation of phospholemman (PLM) on ser68 has been proposed to at least partially mediate cyclic AMP (cAMP) mediated relaxation of arterial smooth muscle. We evaluated the time course of the phosphorylation of phospholemman (PLM) on ser68, myosin regulatory light chains (MRLC) on ser19, and heat shock protein 20 (HSP20) on ser16 during a transient forskolin-induced relaxation of histamine-stimulated swine carotid artery. We also evaluated the dose response for forskolin- and nitroglycerin-induced relaxation in phenylephrine-stimulated PLM-/- and PLM+/+ mice. The time course for changes in ser19 MRLC dephosphorylation and ser16 HSP20 phosphorylation was appropriate to explain the forskolin-induced relaxation and the recontraction observed upon washout of forskolin. However, the time course for changes in ser68 PLM phosphorylation was too slow to explain forskolin-induced changes in force. There was no difference in the phenylephrine contractile dose response or in forskolin-induced relaxation dose response observed in PLM-/- and PLM+/+ aortae. In aortae precontracted with phenylephrine, nitroglycerin induced a slightly, but significantly greater relaxation in PLM-/- compared to PLM+/+ aortae. These data are consistent with the hypothesis that ser19 MRLC dephosphorylation and ser16 HSP20 phosphorylation are involved in forskolin-induced relaxation. Our data sugge st that PLM phosphorylation is not significantly involved in forskolin-induced arterial relaxation., M. K. Meeks, S. Han, A, L. Tucker, C. M. Rembold., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1245. Phthalate metabolites in maternal and cord plasma and their relations to other selected endocrine disruptors and steroids
- Creator:
- Lucie Kolátorová Sosvorová, Jana Vítků, Vavrous, A, Richard Hampl, Karolína Adamcová, Marie Šimková, Antonín Pařízek, Luboslav Stárka, and Michaela Dušková
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- těhotenství, ftaláty, bisfenol A, steroidy, pregnancy, phthalates, bisphenol A, steroids, endocrine disruptor, 14, and 612
- Language:
- English
- Description:
- Endocrine disruptors (EDs) are known to have harmful effects on the human endocrine system; special effort is actually given to the exposure during pregnancy. Humans are usually exposed to a mixture of EDs, which may potentiate or antagonize each other, and the combined effect may be difficult to estimate. The main phthalate monoesters monoethyl-, mono-n -butyl-, monoisobutyl-, monobenzyl-, mono-(2-ethylhexyl)-, mono-(2- ethyl-5-hydroxyhexyl)- and mono-(2-ethyl-5-oxohexyl) phthalate were determined in 18 maternal (37th week of pregnancy) and cord plasma samples using liquid chromatography-tandem mass spectrometry. Previously determined levels of selected bisphenols, parabens and steroids were also considered in this study. In cord blood, there were significantly higher mono-n-butyl phthalate levels than in maternal blood (p=0.043). The results of multiple regression models showed that maternal plasma phthalates were negatively associated with cord plasma androstenedione, testosterone and dehydroepiandrosterone and positively associated with estradiol and estriol. For estriol, a cumulative association was also observed for Σbisphenols. To the best of our knowledge, this is the first pilot study evaluating the effect of prenatal exposure by multiple EDs on newborn steroidogenesis. Our results confirmed phthalate accumulation in the fetal area and disruption of fetal steroidogenesis. This preliminary study highlights the negative impacts of in utero EDs exposure on fetal steroidogenesis., L. Kolatorova, J. Vitku, A. Vavrous, R. Hampl, K. Adamcova, M. Simkova, A. Parizek, L. Starka, M. Duskova., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1246. Physical exercise-induced cardiovascular adjustments are modulated by muscarinic cholinoceptors within the ventromedial hypothalamic nucleus
- Creator:
- Wanner, S. P., Guimarães, J. B., Pires, W., La Guardia, R. B., Haibara, A. S., Marubayashi, U., Coimbra, C. C., and Lima, N. R. V.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, acetylcholin, únava, acetylcholine, fatigue, hypothalamus, methylatropine, 14, and 612
- Language:
- English
- Description:
- The effects of blocking ventromedial hypothalamic nucleus (VMH) muscarinic cholinoceptors on cardiovascular responses were investigated in running rats. Animals were anesthetized with pentobarbital sodium and fitted with bilateral cannulae into the VMH. After recovering from surgery, the rats were familiarized to running on a treadmill. The animals then had a polyethylene catheter implanted into the left carotid artery to measure blood pressure. Tail skin temperature (Ttail), heart rate, and systolic, diastolic and mean arterial pressure were measured after bilateral injections of 0.2 μl of 5 × 10−9 mol methylatropine or 0.15 M NaCl solution into the hypothalamus. Cholinergic blockade of the VMH reduced time to fatigue by 31% and modified the temporal profile of cardiovascular and Ttail adjustments without altering their maximal responses. Mean arterial pressure peak was achieved earlier in methylatropine-treated rats, which also showed a 2-min delay in induction of tail skin vasodilation, suggesting a higher sympathetic tonus to peripheral vessels. In conclusion, muscarinic cholinoceptors within the VMH are involved in a neuronal pathway that controls exercise-induced cardiovascular adjustments. Furthermore, blocking of cholinergic transmission increases sympathetic outflow during the initial minutes of exercise, and this higher sympathetic activity may be responsible for the decreased performance., S. P. Wanner ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1247. Physiological changes after spa treatment: a focus on endocrinology
- Creator:
- Marie Bičíková, Ludmila Máčová, Lucie Kolátorová Sosvorová, Miroslav Hill, Novotný, J, Dana Jandová, and Luboslav Stárka
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- homocystein, homocysteine, neuroactive steroids, serotonin, anxiety-depressive disorder, 14, and 612
- Language:
- English
- Description:
- The paper presents the results of our effort to reveal objective parameters for evaluation of the spa treatment for patients with anxiety-depressive disorders. The study was based on our previous experience with neuroactive steroids and neurosteroids, which play a crucial role in the psychological well-being of patients by maintaining balance of the organism. A total number of 94 steroids were determinated in a group of 70 female patients diagnosed with anxiety-depressive disorders. Patients underwent a month spa treatment while maintaining unchanged medication dosing with SSRI (selective serotonin reuptake inhibitors). The other investigated factors contributing to improving the health of treated subjects were amino-acid homocysteine and serotonin. The blood samples were collected at the beginning and the end of the spa treatment. Serotonin in all patients increased by a relative 23 % (results given as relative differences in percent), while homocysteine decreased by 17.1 %. Statistically significant increases were found in 21 steroids, which indicate activation of the adrenal cortex. It can be assumed, that the overall improvement in the mental condition of patients, which was proved by questionnaire from Knobloch and Hausner, the increase in immune suppressive substances and anti-autoimmune responses, will maintain for a longer time after the spa treatment., M. Bicikova, L. Macova, L. Kolatorova, M. Hill, J. Novotny, D. Jandova, L. Starka., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1248. Physiological response to whole-body vibration in athletes and sedentary subjects
- Creator:
- Gojanovic, B., Feihl, F., Gremion, G., and Waeber, B.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, tělesná cvičení, srdeční rytmus, vibrace, exercises, heart rate, vibration, oxygen consumption, sedentary lifestyle, 14, and 612
- Language:
- English
- Description:
- Whole-body vibration (WBV) is a new exercise method, with good acceptance among sedentary subjects. The metabolic response to WBV has not been well documented. Three groups of male subjects, inactive (SED), endurance (END) and strength trained (SPRINT) underwent a session of side-alternating WBV composed of three 3-min exercises (isometric half-squat, dynamic squat, dynamic squat with added load), and repeated at three frequencies (20, 26 and 32 Hz). VO2, heart rate and Borg scale were monitored. Twenty-seven healthy young subjects (10 SED, 8 SPRINT and 9 END) were included. When expressed in % of their maximal value recorded in a treadmill test, both the peak oxygen consumption (VO2) and heart rate (HR) attained during WBV were greatest in the SED, compared to the other two groups (VO2: 59.3 % in SED vs 50.8 % in SPRINT and 48.0 % in END, p<0.01; HR 82.7 % in SED vs 80.4 % in SPRINT and 72.4 % in END, p<0.05). In conclusions, the heart rate and metabolic response to WBV differs according to fitness level and type, exercise type and vibration frequency. In SED, WBV can elicit sufficient cardiovascular response to benefit overall fitness and thus be a potentially useful modality for the reduction of cardiovascular risk., B. Gojanovic, F. Feihl, G. Gremion, B. Waeber., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1249. Physiological role of FGF signaling in growth and remodeling of developing cardiovascular system
- Creator:
- Krejci, E., Živorad Peševski, Ondřej Naňka, and David Sedmera
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, chick embryo, vasculogenesis, myocyte proliferation, conotruncal banding, 14, and 612
- Language:
- English
- Description:
- Fibroblast growth factor (FGF) signaling plays an important role during embryonic induction and patterning, as well as in modulating proliferative and hypertrophic growth in fetal and adult organs. Hemodynamically induced stretching is a powerful physiological stimulus for embryonic myocyte proliferation. The aim of this study was to assess the effect of FGF2 signaling on growth and vascularization of chick embryonic ventricular wall and its involvement in transmission of mechanical stretchinduced signaling to myocyte growth in vivo . Myocyte proliferation was significantly higher at the 48 h sampling interval in pressure-overloaded hearts. Neither Western blotting, nor immunohistochemistry performed on serial paraffin sections revealed any changes in the amount of myocardial FGF2 at that time point. ELISA showed a significant increase of FGF2 in the serum. Increased amount of FGF2 mRNA in the heart was confirmed by real time PCR. Blocking of FGF signaling by SU5402 led to decreased myocyte proliferation, hemorrhages in the areas of developing vasculature in epicardium and digit tips. FGF2 synthesis is increased in embryonic ventricular cardiomyocytes in response to increased stretch due to pressure overload. Inhibition of FGF signaling impacts also vasculogenesis, pointing to partial functional redundancy in paracrine control of cell proliferation in the developing heart., E. Krejci, Z. Pesevski, O. Nanka, D. Sedmera., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1250. Physiology of nitric oxide in the respiratory system
- Creator:
- Antošová, M., Daniela Mokrá, Pepucha, L., Jana Plevková, Buday, T., Sterusky, M., and Alica Benčová
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, oxid dusnatý, fyziologie, nitric oxide, physiology, nitric oxide synthase, respiratory system, 14, and 612
- Language:
- English
- Description:
- Nitric oxide (NO) is an important endogenous neurotransmitter and mediator. It participates in regulation of physiological processes in different organ systems including airways. Therefore, it is important to clarify its role in the regulation of both airway and vascular smooth muscle, neurotransmission and neurotoxicity, mucus transport, lung development and in the surfactant production. The bioactivity of NO is highly variable and depends on many factors: the presence and activity of NO-producing enzymes, activity of competitive enzymes (e.g. arginase), the amount of substrate for the NO production, the presence of reactive oxygen species and others. All of these can change NO primary physiological role into potentially harmful. The borderline between them is very fragile and in many cases not entirely clear. For this reason, the research focuses on a comprehensive understanding of NO synthesis and its metabolic pathways, genetic polymorphisms of NO synthesizing enzymes and related effects. Research is also motivated by frequent use of exhaled NO monitoring in the clinical manifestations of respiratory diseases. The review focuses on the latest knowledge about the production and function of this mediator and understanding the basic physiological processes in the airways., M. Antosova, D. Mokra, L. Pepucha, J. Plevkova, T. Buday, M. Sterusky, A. Bencova., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public