Diabetes mellitus (DM) has been known for many years to be associated with poor cardiovascular prognosis. Due to the sensitive neuropathy, the coronary artery disease in diabetic patients is frequently asymptomatic. Also twelve leads resting ECG can be within normal limits even in an advanced stage of coronary artery disease. Therefore in addition to the standard ECG other electrocardiographic procedures started to be studied in order to find some typical signs of myocardial damages caused by DM. Repeatedly reported results showed in DM patients without cardiovascular complications the tachycardia, shortening of the QRS and QT intervals, increase of the dispersion of QT interval, decreased amplitudes of depolarization waves, shortened activation time of ventricular myocardium and a flattening of T waves confirmed by the lower value of maximum and minimum in repolarization body surface isopotential maps. Most of these changes are even more pronounced in patients with cardiac autonomic neuropathy. Comparison with similar ECG changes in other diseases suggests that the electrocardiographic changes in DM patients are not specific and that they are particularly caused by an increased tone of the sympathetic nervous system what was indirectly confirmed by the heart rate variability findings in these patients., O. Kittnar., and Obsahuje bibliografii
Tricyclic antidepressant drugs dosulepine (TCA), serotonin selective reuptake inhibitor (SSRI) and prophylactic agent with antidepressant effect lithium carbonicum (Li) have different cardiovascular side-effects. We compared them in the prophylactic therapy of periodic affective disorder in remission with TCA, SSRI and Li. Our previous papers confirmed the most prominent effects of heart electric field parameters in TCA patients (Slavíček et al. 1998). In the present work we studied for the first time the dose-dependent changes of ECG, body surface potential maps (BSPM - parameter DIAM 30, 40) in 43 TCA dosulepine, 40 SSRI citalopram and 30 Li outpatients (Hamilton scale: HAMD£10; age 40±5 years; treated for depressive disorders or bipolar disorders). The daily doses of dosulepine were 50-250 mg, citalopram 20-80 mg, Li plasma levels 0.66±0.08 meq/l. The electrocardiogram (ECG), vectorcardiogram (VCG), and BSPM were measured and calculated by the Cardiag 112.1 diagnostic system. The results have shown a relation between the dose of dosulepine and extremum (maximum and minimum) of depolarization isoarea map in dosulepine, but not in citalopram patients. The repolarization BSPM changes were most pronounced in SSRI patients. Lithium in long-term prophylaxy (1-22 years) caused only minimal ECG BSPM changes. The present results correspond with our previous observations., I. Paclt, J. Slavíček, A. Dohnalová, E. Kitzlerová, K. Pišvejcová., and Obsahuje bibliografii
This paper is devoted to yet unpublished electrode-less methods (ELM) of cell layers impedance measurement based on transformer principle. The main advantage of ELM is elimination uncertainties caused by interface between electrodes and measured electrolyte. The method of avoiding distortion caused by non-ideal transformer transfer function (“deconvolution”) and errors caused by residual voltage is described. The modification of original transformer based method allowing to measure an impedance of inserted object is proposed. Results of several calibration measurements confirming the proper function of ELM including example of transepithelial resistance of cells layer are presented. Crucial parts of measuring system and recommendation for their realization are included., J. Krůšek, S. Ďáďo., and Obsahuje bibliografii
To evaluate the direct effects of a barbiturate on cerebral functions without its influence on brain perfusion pressure, circulatory hormones and metabolites, the electroencephalogram (EEG) was studied in the isolated rat head. Male Wistar rats were anesthetized, and EEG electrodes were inserted into the cranium. A Krebs-Ringer bicarbonate buffer solution containing heparinized rat whole blood, 20 mmol/l glucose, 200 mmol/l mannitol and 0.1 mg/ml dexamethasone was used for the perfusate. The bilateral common carotid arteries were cannulated, pumped at a rate of 6 ml/min and the head was isolated. The venous effluent was reoxygenated and recirculated into the brain. Twenty-five min after isolation of the heads pentobarbital was added to the perfusate at concentrations of 0.1, 0.5 and 2.5 mg/ml. EEG was recorded before and during perfusion. EEG activity could be recorded for more than 25 min after the beginning of perfusion. EEG activity gradually declined from 42±5 μV before perfusion (in vivo) to 4±1 μV at 25 min after the beginning of perfusion. Then, 3 min after the addition of pentobarbital, the EEG activity became significantly higher in the high dose groups; 12±3 μV in the 0.5 mg/ml group (p<0.05) and 12±1 μV in 2.5 mg/ml group (p<0.05) compared with the group without pentobarbital (2±2 μV). The present study suggests that a barbiturate has mitigating effects on the brain damage induced by the in vitro brain perfusion., A. Tagawa, O. Mokuda, Y. Sakamoto, N. Shimizu., and Obsahuje bibliografii
In the mammalian autonomic nervous system, tonic and phasic neurons can be differentiated on firing patterns in response to long depolarizing current pulse. However, the similar firing patterns in the somatic primary sensory neurons and their functional significance are not well investigated. Here, we identified two types of neurons innervating somatic sensory in rat dorsal root ganglia (DRG). Tonic neurons fire action potentials (APs) in an intensity-dependent manner, whereas phasic neurons typically generate only one AP firing at the onset of stimulation regardless of intensity. Combining retrograde labeling of somatic DRG neurons with fluorescent tracer DiI, we further find that these neurons demonstrate distinct changes under inflammatory pain states induced by complete Freund’s adjuvant (CFA) or bee venom toxin melittin. In tonic neurons, CFA and melittin treatments significantly decrease rheobase and AP durations (depolarization and repolarization), enhance amplitudes of overshoot and afterhyperpolarization (AHP), and increase the number of evoked action potentials. In phasic neurons, however, the same inflammation treatments cause fewer changes in these electrophysiological parameters except for the increased overshoot and decreased AP durations. In the present study, we find that tonic neurons are more hyperexcitable than phasic neurons after peripheral noxious inflammatory stimulation. The results indicate the distinct contributions of two types of DRG neurons in inflammatory pain., Y.-Q. Yu, X.-F. Chen, Y. Yang, F. Yang, J. Chen., and Obsahuje bibliografii
This study has observed possible effect of ellagitannins - compounds from pomegranate on process of steroidogenesis in ovaries. The aim of the study was to investigate the possible effect of punicalagin on secretion of steroid hormones - progesterone, androstenedione, testosterone and 17β-estradiol by ovarian fragments of rabbits in vitro. Ovarian fragments from sexually mature female New Zealand white rabbits (n=20) were incubated without (control group) or with punicalagin at various doses 1, 10 and 100 μg.ml−1 for 24 h. Hormones were evaluated by ELISA (The Enzyme-Linked Immunosorbent Assay). Data showed that progesterone and 17β-estradiol (but not androstenedione and testosterone) release by rabbit ovarian fragments was significantly affected by punicalagin addition at various doses. Punicalagin (at 100 μg.ml-1) significantly (P<0.05) increased progesterone secretion. On the other hand, the release of 17β-estradiol was significantly (P<0.005) decreased by punicalagin addition (at 10 μg.ml-1). Our results suggest that punicalagin could have dose-dependent impact on secretion of steroid hormones progesterone and 17β-estradiol by rabbit ovarian fragments and it may be effector in process of ovarian steroidogenesis., D. Packova, A. A. Carbonell-Barrachina, A. Kolesarova., and Obsahuje bibliografii
There is an increasing eviden ce linking dysbalance between various proinflammatory mediators and higher risk of cardiovascular events and pathologies. Likewise, some of the cardiovascular diseases lately ap peared to have an autoimmune component. Interleukin-1 (IL-1), a master regulator of diverse inflammatory processes in higher eukaryotes and the key player in numerous autoimmune disorders including rheumatoid arthritis, diabetes mellitus or systemic sclerosis, has recently been proved to be involved in development of several cardiovascular diseases as well. This report aims to give a summary on current knowledge about the IL-1 signaling pathways and about the implication of IL-1 and the IL-1 receptor antagonist (IL-1Ra) in some of the diseases of the cardiovascular system., B. Vicenová ... [et al.]., and Obsahuje seznam literatury
The rat strain transgenic for the murine Ren-2 renin gene (TGR) is defined as a monogenic model of angiotensin II-dependent hypertension with endogenous activation of the renin-angiotensin system. Homozygous males TGR develop malignant hypertension with a strong salt-sensitive component. These animals show severe hypertension, proteinuria and high mortality. Morphological changes of renal parenchyma correspond to chronic ischemic glomerular changes. Heterozygous TGR develop only mild hypertension and thus provide a more suitable model of hypertension regarding to clinic al studies. Within the renal parenchyma, secondary focal segmental glomerulosclerosis (FSGS) predominates. High-salt diet in heterozygous animals induces transition from benign to malignant phase of hypertension. In this case, ischemic glomerular changes are superimposed on preexisting secondary FSGS. In the regression model of hypertension (late-onset treatment) the effect of salt intake is attenuated. In homozygous TGR, early selective ET A receptor blockade decreased blood pressure and ameliorated end-organ damage. Late selective ET A receptor blockade reduced podocyte injury despite final severe hypertension. Survival rate was markedly improved in both regimens with ETA selective blockade, while there was only partial improvement with early non-selective blockade. Both bosentan and atrasentan decreased ET-1 levels in both regimens. In heterozygous TGR, early and late ETA treatment substantially while ETA/ETB treatment partially improved survival rate. Significant effect on BP was found with early and late ETA blockade, while ETA/ETB blockade had no effect. Bosentan and at rasentan similarly decreased ET-1 levels on both regimens. In conclusion, selective ETA receptor blockade is superior to nonselective ETA/ETB receptor blockade in attenuating hypertension and end-organ damage. Its effect is more pronounced when applied early in the life., Z. Vernerová ... [et al.]., and Obsahuje seznam literatury
Endotoxin lipopolysaccharide (LPS) affects the ruminant health and animal performance. The main purposes of this study were to investigate the potential effects of GH/IGF system and lipoprotein lipase (LPL) concentration on resistance the circulating LPS concentration increased in liver with high concentrate diet treatment. Non- lactating goats were randomly allocated to two groups : a high -concentrate diet (HCD ) or a low - concentrate diet (LCD ) in cross over design and the blood collection at different time points after feeding at the end of the experiment. The average rumen pH was significantly reduced (P<0.05) , but the duration with pH was not more than 120 min in the HCD group. T he plasma LPL concentration w as significantly raised (P<0.05) . However, fr om 2 h onwards, LPS concentration was significantly reduced (P<0.0 1) in the H CD group compared with LCD group. In addition , the plasma IGF1 concentration and the hepatic i nsulin -like growth factor -1 receptor ( IGF1R) mRNA expression were markedly reduced (P<0.0 5). However, g rowth hormone (GH) secretion at 15, 30, and 45 min after feeding and growth hormone receptor (GHR) mRNA expression in the liver was significantly increased (P<0.05) in HCD group. The correlation analysis showed that the plasma LPL concentration was positive ly correlated with hepatic GHR mRNA expression (P<0.05) . Conversely, the plasma LPS concentration was negatively correlate d with LPL concentration (P<0.05). These findings reveal that alterations in GH/IGF system function in response to a hi gh -concentrate diet are accompanied by corresponding changes in systemic LPL in non -lactating goats ’ liver in presence of endogenous LPS stress., Z. L. Xie, P. S. Ye, S. K. Zhang, Y. S. Zhang, X. Z. Shen., and Obsahuje bibliografii
Left ventricular assist devices (LVAD), currently used in treatment of terminal heart failure, are working on principle of rotary pump, which generates continuous blood flow. Non-pulsatile flow is supposed to expose endothelial cells to high stress and potential damage. Therefore, we investigated longitudinal changes in concentration of circulating endothelial microparticles (EMP) as a possible marker of endothelial damage before and after implantation of LVAD. Study population comprised 30 patients with end-stage heart failure indicated for implantation of the Heart Mate II LVAD. Concentrations of microparticles were measured as nanomoles per liter relative to phosphatidylserine before and 3 months after implantation. At 3 months after implantation we observed significant decrease in concentration of EMP [5.89 (95 % CI 4.31-8.03) vs. 3.69 (95 % CI 2.70-5.03), p=0.03] in the whole group; there was no difference observed between patients with ischemic etiology of heart failure (n=18) and with heart failure of non-ischemic etiology (n=12). In addition, heart failure etiology had no effect on the rate of EMP concentration decrease with time. These results indicate possibility that LVAD do not cause vascular damage 3 months after implantation. Whether these results suggest improvement of vascular wall function and of endothelium is to be proved in long-term studies., P. Ivak, J. Pitha, P. Wohlfahrt, I. Kralova Lesna, P. Stavek, Z. dorazilova, J. Stepankova, J. Maly, M. Pokorny, I. Netuka., and Obsahuje bibliografii