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1212. Sildenafil is more selective pulmonary vasodilator than prostaglandin E1 in patients with pulmonary hypertension due to heart failure
- Creator:
- Hikmet Al-Hiti, Vojtěch Melenovský, Petr Syrovátka, Jiří Kettner, Ivan Málek, and Josef Kautzner
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, srdeční selhání, hemodynamika, prostaglandiny, heart failure, hemodynamics, prostaglandins, pulmonary vascular resistance, sildenafil, prostaglandin E1, 14, and 612
- Language:
- English
- Description:
- In some patients, heart failure (HF) is associated with increased pulmonary vascular resistance (PVR). The magnitude and the reversibility of PVR elevation affect the HF management. Sildenafil has been recently recognized as potent PVR-lowering drug in HF. The aim of the study was to compare hemodynamic effects and pulmonary selectivity of sildenafil to prostaglandin E1(PGE1). Right-heart catheterization was performed in 13 euvolemic advanced HF patien ts with elevated PVR (6.3±2 Wood's units). Hemodynamic parameters were measured at the baseline, during i.v. infusion of PGE1 (alprostadil 200 ng·kg-1·min-1 ) and after 40 mg oral do se of sildenafil. Both drugs similarly reduced systemic vascular resistance (SVR), but sildenafil had higher effect on PVR (-28 % vs. -49 %, p=0.05) and transpulmonary pressu re gradient than PGE1. The PVR/SVR ratio - an index of pulmonary se lectivity, did not change after PGE1(p=0.7) but it decreased by -32 % (p=0.004) after sildenafil. Both drugs similarly reduced pulmonary artery mean and wedge pressures and increa sed cardiac index (+27 % and +28 %). Sildenafil led more often to transplant-acceptable PVR while causing smaller drop of mean systemic pressure than PGE1. In conclusion, vasodilatatory effects of sildenafil in patients with heart failure are more pronounced in pulmonary than in systemic circulation., H. Al-Hiti ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1213. Silymarin component 2,3-dehydrosilybin attenuates cardiomyocyte damage following hypoxia/reoxygenation by limiting oxidative stress
- Creator:
- Gabrielová, E., Vladimír Křen, Martin Jabůrek, and Martin Modrianský
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, silymarin, dehydrosilybin, neonatal rat cardiomyocytes, postconditioning, reactive oxygen species, 14, and 612
- Language:
- English
- Description:
- Ischemic postconditioning and remote conditioning are potentially useful tools for protecting ischemic myocardium. This study tested the hypothesis that 2,3-dehydrosilybin (DHS), a flavonolignan component of Silybum marianum , could attenuate cardiomyocyte damage following hypoxia/ reoxygenation by decreasing the generation of reactive oxygen species (ROS). After 5-6 days of cell culture in normoxic conditions the rat neonatal cardiomyocytes were divided into four groups. Control group (9 h at normoxic conditions), hypoxia/ reoxygenation group (3 h at 1 % O2 , 94 % N2 and 5 % CO2 followed by 10 min of 10 μmol·l -1 DHS and 6 h of reoxygenation in normoxia) and postconditioning group (3 h of hypoxia, three cycles of 5 min reoxygenation and 5 min hypoxia followed by 6 h of normoxia). Cell viability assess ed by propidium iodide staining was decreased after DHS treatment consistent with increased levels of lactatedehydrogenase (LDH) after reoxygenation. LDH leakage was significantly reduced when cardiomyocytes in the H/Re group were exposed to DHS. DHS treatment reduced H2O2 production and also decreased the generation of ROS in the H/Re group as evidenced by a fluorescence indicator. DHS treatment reduces reoxygenation-induced injury in cardiomyocytes by attenuation of ROS generation, H2O2 and protein carbonyls levels. In addition, we found that both the postconditioning protocol and the DHS treatment are associated with restored ratio of phosphorylated/total protein kinase C epsilon, relative to the H/Re group. In conclusion, our data support the protective role of DH S in hypoxia/reperfusion injury and indicate that DHS may act as a postconditioning mimic., E. Gabrielová, V. Křen, M. Jabůrek, M. Modrianský., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1214. Similar effects of lamotrigine and phenytoin against cortical epileptic foci in immature rats
- Creator:
- Klára Bernášková and Pavel Mareš
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, mozková kůra, cerebral cortex, epileptic focus, bicuculline methiodide, immature rat, antiepileptic drugs, 14, and 612
- Language:
- English
- Description:
- Action of antiepileptic drugs in immature brain may differ from that in adult brain. The aim of our study was to study an anticonvulsant action of lamotrigine and phenytoin, i.e. two drugs active against partial seizures in adult experimental animals as well as human patients, in a model of simple partial seizures in immature rats. Epileptic foci were induced by local application of bicuculline methiodide on sensorimotor cortical area of 12-dayold rat pups. The animals were pretreated with lamotrigine (LTG, 10 or 20 mg/kg i.p.) or phenytoin (PHT, 15, 30 or 60 mg/kg i.p.). Control rats for LTG received saline, controls for PHT solvent composed of propyleneglycol, ethanol and water. Influence of either drug on interictal activity was negligible. High doses of both LTG and PHT suppressed the transition into ictal phases and shortened the duration of persisting seizures. The tricomponent solvent exhibited moderate activity against ictal activity if compared with saline controls. The two drugs exhibited similar action in our model, i.e. the suppression of secondary generalization from epileptic focus. This action is comparable to that described for human patients and adult experimental animals. In favor of lamotrigine speaks the absence of serious side effects., K. Bernášková, P. Mareš., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1215. Simultaneous decrease of plasma obestatin and ghrelin levels after a high-carbohydrate breakfast in healthy women
- Creator:
- Dana Sedláčková, Ivana Dostálová, Vojtěch Hainer, Beranová, L., Hana Kvasničková, Martin Hill, Martin Haluzík, and Jara Nedvídková
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, endokrinologie, biochemie, endocrinology, biochemistry, obestatin, total ghrelin, acyl ghrelin, desacyl ghrelin, carbohydrate breakfast, 14, and 612
- Language:
- English
- Description:
- Ghrelin is a gut peptide produced mainly by stomach, well known to induce appetite stimulatory actions. Obestatin, a recently identified peptide derived from preproghrelin, was initially described to antagonize stimulatory effect of ghrelin on food intake. The postprandial response of obestatin and its relationship with ghrelin in humans remains unknown. We therefore investigated the postprandial response of obestatin and total ghrelin, acyl and desacyl ghrelin and neuropeptide Y (NPY) to a high-carbohydrate breakfast (1 604 kJ) in eight healthy women (age: 24.2±0.82 years; BMI 21.6±0.61 kg/m2). Blood samples were collected before the meal, and 30, 60, 90, 120 and 150 min after the breakfast consumption. Postprandial plasma obestatin concentrations significantly decreased compared with preprandial levels as well as total ghrelin concentrations and reached the lowest values 90 and 120 min after the meal consumption, respectively (p 0.05). Plasma acyl and desacyl ghrelin concentrations decreased after the breakfast and reached lowest values in 30 and 60 min, respectively (p<0.05). Plasma NPY concentrations were lower than preprandial levels 90 and 150 min after consuming breakfast (p<0.05). In conclusion, we demonstrated in healthy young women that plasma obestatin concentrations decrease similarly to ghrelin after a high-carbohydrate breakfast., D. Sedláčková, I. Dostálová, V. Hainer, L. Beranová, H. Kvasničková, M. Hill, M. Haluzík, J. Nedvídková., and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1216. Simvastatin alleviates myocardial contractile dysfunction and lethal ischemic injury in rat heart independent of cholesterol-lowering effects
- Creator:
- Adriana Adameová, Anna Harčárová, Jana Matejíková, Dezider Pancza, Magdaléna Kuželová, Slávka Čarnická, Peter Švec, Monika Barteková, Ján Styk, and Ravingerová, T.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, cholesterol, statiny, srdce, ischemie, statins, heart, ischemia, pleiotropic effects, 14, and 612
- Language:
- English
- Description:
- a1_Statins, the inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, are most frequently used drugs in the prevention of coronary artery disease due to their cholesterol- lowering activity. However, it is not exactly known whether these effects of statins or those independent of cholesterol decrease account for the protection ag ainst myocardial ischemia- reperfusion (I/R) injury. In this study, we investigated the effect of 5-day treatment with simvastatin (10 mg/kg) in Langendorff- perfused hearts of healthy control (C) and diabetic- hypercholesterolemic (D-H; strept ozotocin + high fat-cholesterol diet, 5 days) rats subjected to 30-min global ischemia followed by 40-min reperfusion for the examination of postischemic contractile dysfunction and reperfusion-induced ventricular arrhythmias or to 30-min (left anterior descending) coronary artery occlusion and 2-h reperfusion for the infarct size determination (IS; tetrazolium stai ning). Postischemic recovery of left ventricular developed pressu re (LVDP) in animals with D-H was improved by simvastatin therapy (62.7±18.2 % of preischemic values vs. 30.3±5.7 % in the untreated D-H; P<0.05), similar to the values in the simvastatin-treated C group, which were 2.5-fold higher than those in the untreated C group. No ventricular fibrillation occurred in the simvastatin-treated C and D-H animals during reperf usion. Likewise, simvastatin shortened the duration of ventri cular tachycardia (10.2±8.1 s and 57.8±29.3 s in C and D-H vs. 143.6±28.6 s and 159.3±44.3 s in untreated C and D-H, respectively, both P<0.05). The decreased arrhythmogenesis in the simvastatin-treated groups correlated with the limitation of IS (in % of risk area) by 66 % and 62 % in C and D-H groups, respectively. However, simvastatin treatment decreased plasma cholesterol levels neither in the D-H animals nor in C., a2_The results indicate that other effects of statins (independent of cholesterol lowering) are involved in the improvement of contractile recovery and attenuation of lethal I/R injury in both, healthy and diseased individuals., A. Adameová, A. Harčárová, J. Matejíková, D. Pancza, M. Kuželová, S. Čarnická, P. Švec, M. Barteková, J. Styk, T. Ravingerová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1217. Simvastatin decreased coenzyme Q in the left ventricle and skeletal muscle but not in the brain and liver in L-NAME-induced hypertension
- Creator:
- Jarmila Kucharská, Anna Gvozdjáková, and Fedor Šimko
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- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, hypertenze, hypertension, simvastatin, NO-deficient hypertension, tissue coenzyme Q, L_NAME, 14, and 612
- Language:
- English
- Description:
- Inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (statins) have been proven to reduce effectively cholesterol level and morbidity and mortality in patients with coronary heart disease and/or dyslipoproteinemia. Statins inhibit synthesis of mevalonate, a precursor of both cholesterol and coenzyme Q (CoQ). Inhibited biosynthesis of CoQ may be involved in some undesirable actions of statins. We investigated the effect of simvastatin on tissue CoQ concentrations in the rat model of NO-deficient hypertension induced by chronic L-NAME administration. Male Wistar rats were treated daily for 6 weeks with L-NAME (40 mg/kg) or with simvastatin (10 mg/kg), another group received simultaneously L-NAME and simvastatin in the same doses. Coenzyme Q9 and Q10 concentrations were analyzed by high performance liquid chromatography. L-NAME and simvastatin alone had no effect on CoQ concentrations. However, simultaneous application of L-NAME and simvastatin significantly decreased concentrations of both CoQ homologues in the left ventricle and slightly decreased CoQ9 concentration in the skeletal muscle. No effect was observed on CoQ level in the liver and brain. We conclude that the administration of simvastatin under the condition of NO-deficiency reduced the level of CoQ in the heart and skeletal muscle what may participate in adverse effect of statins under certain clinical conditions., J. Kucharská, A. Gvozdjáková, F. Šimko., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1218. Skin blood flowmotion and microvascular reactivity investigation in hypercholesterolemic patients with out clinically manifest arterial diseases
- Creator:
- Rossi, M., Carpi, A., Di Maria, C., Franzoni, F., Galetta, F., and Santoro, G.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, hypercholesterolémie, acetylcholin, Fourierova analýza, physiology, hypercholesterolemia, acetylcholine, Fourier analysis, endothelial function, laser Doppler flowmetry, flowmotion, sodium nitroprusside, 14, and 612
- Language:
- English
- Description:
- Fourier spectral analysis of fore arm skin laser Doppler flowmetry (LDF) signal was performed in fifteen hypercholesterolemic patients (HP), without clinically manifest arterial diseases, and in fifteen age-matched healthy control subjects (CS), in order to investigate skin blood flowmotion (SBF). The LDF frequency intervals studied were: 0.01-1.6 Hz total spectrum, as well as 0.01-0.02 Hz (endothelial), 0.02-0. 06 Hz (sympathetic), 0.06-0.2 Hz (myogenic), 0.2-0.6 Hz (respiratory) and 0.6-1.6 Hz (cardiac). Skin microvascular reactivity (MVR ) to acetylcholine (ACh) and to sodium nitroprusside (SNP) iontophoresis was also investigated. HP showed a lower post-ACh increase in power spectral density (PSD) of the 0.01-0.02 Hz SBF subinterval compared to CS (1.80±1.73 PU 2 /Hz vs 3.59±1.78 PU 2 /Hz, respectively; p<0.005), while they did not differ in MVR from CS. In eleven HP the 0.01-0.02 Hz SBF subinterval showed a higher post-ACh PSD increase near to the statistical significance after 10 weeks of rosuvastatin therapy (10 mg/day) compared to pretreatment test (3.04±2.95 PU 2 /Hz vs 1.91±1.94 PU 2 /Hz; p=0.07). The blunted post-ACh increase in PSD of the 0.01-0.02 Hz SBF subinterval in HP suggests a skin endothelial dysfunction in these patients. This SBF abnormality showed a tendency to improve after rosuvastatin therapy in eleven treated patients., M. Rossi ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1219. Sleep microstructure is not altered in children with attention-deficit/hyperactivity disorder (ADHD)
- Creator:
- Iva Příhodová, Ivo Paclt, David Kemlink, and Soňa Nevšímalová
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, attention-deficit/hyperactivity disorder, nocturnal videopolysomnography, cyclic alternating pattern, 14, and 612
- Language:
- English
- Description:
- The high rate of occurrence of sleep disturbances in children with attention-deficit/hyperactivity disorder (ADHD) prompted the idea that structural and neurotransmitter changes might give rise to specific sleep pattern abnormalities. The aim of this study was to evaluate the microstructure of sleep in children with ADHD who had no polysomnographically diagnosed sleep disorder, had never been treated for ADHD, and were free from any psychiatric comorbidity. Participants were 14 patients with ADHD (12 boys and 2 girls aged 7-12 years, mean age 9.6±1.6). ADHD was diagnosed according to DSM-IV criteria (Diagnostic and statistical manual of mental disorders). Psychiatric comorbidities were ruled out by detailed psychiatric examination. The patients underwent two consecutive overnight video-polysomnographic (PSG) recordings, with the sleep microstructure (cyclic alternating pattern – CAP) scoring during the second night. The data were compared with age- and sex-matched controls. Sleep microstructure analysis using CAP revealed no significant differences between the ADHD group and the controls in any of the parameters under study. In conclusions, no ADHD-specific alterations were found in the sleep microstructure., I. Příhodová ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1220. Slow breathing training reduces resting blood pressure and the pressure responses to exercise
- Creator:
- Jones, C. U., Sangthong, B., Pachirat, O., and Jones, D. A.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, hypertenze, srdeční rytmus, hypertension, heart rate, slow breathing training, muscle pressor response, heart rate variability, 14, and 612
- Language:
- English
- Description:
- Slow breathing training reduces resting blood pressure, probably by modifying central autonomic control, but evidence for this is lacking. The pressor response to static handgr ip exercise is a measure of autonomic control and the aim of this study was to determine whether slow breathing training modulates the pressor responses to exercise of untrained muscles. Twenty hypertensive patients trained for 8 weeks, 10 with unloaded slow breathing (Unloaded) and 10 breathing against an inspiratory load of 20 cm H 2 O (Loaded). Ten subjects were untrained controls. Subjects performed a 2 min handgrip pressor test (30 % MVC) pre - and post- training, and blood pressure and heart rate (HR) were measured before the contraction, at the end and following 2 min recovery. Resting systolic (sBP) and HR were reduced as a result of tra ining, as reported previously. After training there was both a smaller pressor response to hand grip exercise and a more rapid recovery of sBP and HR compared to pre -training. There were no changes in the Controls and no differences between the Unloaded and Loaded groups. Combining the two training groups, the sBP response to handgrip exercise after training was reduced by 10 mm Hg (95 % CI: - 7, - 13) and HR by 5 bpm (95 % CI: - 4, - 6), all p<0.05. These results are consistent with slow breathing training modifying central mechanisms regulating cardiovascular function., C. U. Jones, B. Sangthong, O. Pachirat, D. A. Jones., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public