The saccadic eye movement related potentials (SEMRPs) enable to study brain mechanisms of the sensorimotor integration. SEMRPs provide insight into various cognitive mechanisms related to planning, programming, generation and execution of the saccadic eye movements. SEMRPs can be used to investigate pathophysiological mechanisms of several disorders of the central nervous system. Here we shortly summarize basic findings concerning the significance of SEMRP components, their relationship to the functional brain asymmetry and visual attention level as well as changes related to certain neuropsychological disorders., F. Jagla, M. Jergelová, I. Riečanský., and Obsahuje bibliografii a bibliografické odkazy
To determine the effect of saturated hydrogen saline on lipopolysaccharide (LPS)-induced acute liver dysfunction, rats were divided into control, LPS, and LPS plus saturated hydrogen saline (LPS+H 2 ) groups. Treatment with saturated hydrogen saline prolonged the median su rvival time and reduced liver dysfunction. Moreover, saturated hydrogen saline significantly reduced pathological alterations in liver tissues, the number of ballooned hepatocytes, serum tumor necrosis factor (TNF)- α and interleukin (IL)-6 levels, and myeloperoxidase (MPO) and malondialdehyde (MDA) levels in liver tissues (P<0.05). Cell apoptosis was detected in liver tissues after LPS treatment, and attenuated by saturated hydrogen saline treatment. Saturated hydrogen saline also decreased phosphorylated extracellular signal-regulated kinase (p-ERK), phosphorylated Jun kinase (p-JNK), nuclear factor-kappa B (NF- κ B), and second mitochondria-derived activator of caspase (Smac) levels, and increased p38 activation (P<0.05). Thus, saturated hydrogen saline may attenuate LPS-induced acute liver dysfunction in rats, possibly by reducing inflammation and cell apoptosis. Mitogen- activated protein kinase (MAPK), NF- κ B, and Smac may contribute to saturated hydrogen saline-mediated liver protection., X.-F. Xu, J. Zhang., and Obsahuje seznam literatury
a1_Young intact (18 days of age) and adult ovariectomized (OV-X, ovariectomized between 21 to 24 days of age) C3H/Di mice were used to measure the estrogenicity on the basis of the growth response of mammary epithelial structures and weight of the uterus. The percentage area of the mammary fat pad occupied by mammary epithelial structures was progressively increased by 17ß estradiol from dose 0.001 µg.d-1. The maximum effective dose of estradiol was 0.01 µg.d-1 and the dose 10 µg.d-1 of estradiol decreased mammary size to control levels (inverted-U-shaped dose-response curve). Progesterone alone progressively stimulated mammary growth in young intact females from dose 125 µg.d-1, in adult OV-X animals from dose 1000 µg.d-1. Both in young intact and adult OV-X animals, uterine weight progressively increased during estradiol treatment. Progesterone alone had no effect on uterine weight in young intact animals; in adult OV-X animals, uterine weight was increased starting from dose 250 µg.d-1. Progesterone acted synergistically with estradiol to produce higher mammary growth than that in females treated with estradiol alone. The effects of a combination of estradiol plus progesterone in the mammary gland were mimicked by norethindrone acetate and inhibited by cortisol in both young intact and adult OV-X animals. Testosterone inhibited estradiol plus progesterone stimulated growth of mammary gland only in OV-X animals, but stimulated uterine weights in both young intact and adult OV-X animals. Spleen weight and size of mammary lymph nodes were not affected by estradiol, progesterone, norethindrone acetate or testosterone, but were decreased by cortisol. Cortisol also decreased the percent area of the mammary fat pad occupied by mammary epithelial structures, but had no effect on weight of the uterus. These results show that bioassay of estrogenicity in females is not specific., a2_Mammary and uterine growth is stimulated not only by estrogens but also by progesterone and testosterone, respectively. ., J. Škarda., and Obsahuje bibliografii
a1_Young intact (18 days old) and adult castrated males of CBA and C3H/Di mice were used for measuring the estrogenicity on the basis of growth response of mammary epithelial structures and the weight of seminal vesicles. It was demonstrated that heavier young males had disproportionally heavier seminal vesicles (sex steroid-responsive organs) than small animals at day 33 of age (that is on the day when experimental animals were killed and organs dissected). However, the weight of the spleen (sex steroid-nonresponsive organ) was proportionally related to body weight. To minimize variability in hormone responsiveness, all animals were weighed at the age of 18 days and only males weighing 8±1 g were used for hormone treatment. The percentage area of mammary fat pad occupied by mammary epithelial structures was progressively increased by 17ß estradiol from dose 0.01 µg.d-1. The maximum effective dose of estradiol was 0.1 µg.d-1 and dose 10 µg.d-1 of estradiol decreased mammary size to control level (inverted-U-shaped dose-response curve). Progesterone alone stimulated mammary growth only in high doses (500 µg.d-1 and higher) in young intact males, but had no effect on mammary growth in adult castrated animals. In young intact males, estradiol alone, or progesterone alone decreased the weight of seminal vesicles. No such inhibitory effect of these hormones was noted in adult castrated males. Progesterone acted synergistically with estradiol to produce higher mammary growth compared to that in males treated with estradiol alone. In the presence of progesterone seminal vesicles weight was decreased by estradiol given in such low doses as 0.001 µg.d-1 of estradiol, which is 10 times lower than that effective in animals treated with estradiol alone. On the other hand, in the adult castrated males a combination of estradiol plus progesterone stimulated seminal vesicles weight., a2_The effects of a combination of estradiol plus progesterone in the mammary gland were mimicked by norethindrone acetate (a synthetic steroid exhibiting progestantial and estrogenic activities) and inhibited by both testosterone and cortisol. Estradiol, progesterone, norethindrone acetate, or testosterone did not affect spleen weight and size of mammary lymph nodes. However, cortisol significantly decreased not only spleen weights but also size of mammary lymph nodes. These results show that simultaneous evaluation of mammary gland growth, seminal vesicles, and the spleen weight in the same animal is suitable for bioassay of estrogenicity as well as for detection of androgenic and antiandrogenic activities., J. Škarda., and Obsahuje bibliografii
Monoaminergic neurotransmitter 5-hydroxytryptamine (5-HT), also known as serotonin, plays im portant roles in modulating the function of the olfactory system. However, thus far, the knowledge about 5-HT and its receptors in olfactory receptor neurons (ORNs) and their physiological role have not been fully characterized. In the present study, reverse transcription- polymerase chain reaction (RT-PCR) analysis revealed the presence of 5-HT 1A and 5-HT 1B receptor subtypes in mouse olfactory epithelium at the mRNA level. With subtype selective antibodies and standard immunohistochemical techniques, both receptor subtypes were found to be positively labeled. To further elucidate the molecular mechanisms of 5-HT act on the peripheral olfactory transduction, the whole-cell patch clamp techniques were used on freshly isolated ORNs. We found that 5-HT decreased the magnitude of outward K + current in a dose- dependent manner and these inhi bitory effects were markedly attenuated by the 5-HT 1A receptor blocker WAY-100635 and the 5-HT 1B receptor antagonist GR55562. These data suggested that 5-HT may play a role in the modu lation of peripheral olfactory signals by regulating outward potassium currents, both 5-HT 1A and 5-HT 1B receptors were involved in this regulation., S. Gao, ... [et al.]., and Obsahuje seznam literatury
a1_The decreased oxidizability of plasma lipoproteins is related to the increased vitamin E intake and its association with a relatively lower incidence of coronary heart disease has been proposed. We investigated the effect of the in vivo vitamin E supplementation on the oxidizability of serum lipids in patients with ischemic heart disease and a moderate hypercholesterolemia. Thirty-two patients (16 males and 16 postmenopausal women) participated in this placebo-controlled, randomized trial. They were treated with 400 mg vitamin E/day for 6 weeks. The copper-induced serum lipid oxidizability ex vivo was assessed by measuring conjugated diene formation at 245 nm. We also measured vitamin E, malondialdehyde (MDA) and uric acid concentrations in the plasma. Because of observed significant differences in parameters of serum lipid oxidizability (lag time and maximal rate of oxidation), plasma a-tocopherol and MDA levels between male patients and postmenopausal women supplemented with vitamin E, the results were compared between both genders. Six weeks of vitamin E supplementation significantly increased plasma vitamin E levels (by 87 %) in male patients but in postmenopausal women only by 34 %. Concomitantly with increased plasma levels of vitamin E the decrease in plasma MDA levels was observed in male patients (decrease by 20 %; p=0.008), but in postmenopausal women the decrease did not attain statistical significance. Plasma uric acid levels were not apparently changed in placebo or vitamin E supplemented groups of patients. The changes in ex vivo serum lipid oxidizability after vitamin E, supplementation have shown a significantly prolonged lag time (by 11 %; p=0.048) and lowered rate of lipid oxidation (by 21 %; p=0.004) in male patients in comparison with postmenopausal women., a2_Linear regression analysis revealed a significant correlation between plasma vitamin E levels and the lag time (r=0.77; p=0.03) and the maximal rate of serum lipid oxidation (r=-0.70; p=0.05) in male patients. However, in postmenopausal women the correlations were not significant. We conclude that 400 mg vitamin E/day supplementation in patients with ischemic heart disease and a moderate hypercholesterolemia influenced favorably ex vivo serum lipid oxidation of male patients when compared with postmenopausal women. The observed differences between both genders could be useful in the selection of the effective vitamin E doses in the prevention of coronary heart disease., A. Nagyová, V. Mongiellová, Z. Krivošíková, P. Blažíček, V. Spustová, M. Gajdoš, R. Dzúrik., and Obsahuje bibliografii
The Morris water maze (MWM) is one of the most common tasks used to assess spatial learning and memory ability in rodents. Genetic strain and gender are two prominent variants that influence spatial performance. Although it was reported that ICR (Institute of Cancer Research) mice exhibited an unchanged baseline performance in the training phase of the MWM task, this outbred strain has been widely used in learning and memory studies, and little is known regarding the effects of sex on behavioral performance. In this study, we demonstrated that both male and female ICR mice could complete the MWM task. Furthermore, a significant sex difference was observed, with females having shorter escape latencies and longer durations in the target quadrant in both the acquisition and test phases. Our findings emphasize the necessity of careful examination of not only the strain effect on behavioral performance but also the sex effect., J.-F. Ge, ... [et al.]., and Obsahuje seznam literatury
The effect of three-day fasting on cardiac ischemic tolerance was investigated in adult male Wistar rats. Anesthetized open-chest animals (pentobarbitone 60 mg/kg, i.p.) were subjected to 20-min left anterior descending coronary artery occlusion and 3-h reperfusion for infarct size determination. Ventricular arrhythmias were monitored during ischemia and at the beginning (3 min) of reperfusion. Myocardial concentrations of beta-hydroxybutyrate and acetoacetate were measured to assess mitochondrial redox state. Short-term fasting limited the infarct size (48.5±3.3 % of the area at risk) compared to controls (74.3±2.2 %) and reduced the total number of premature ventricular complexes (12.5±5.8) compared to controls (194.9±21.9) as well as the duration of ventricular tachycardia (0.6±0.4 s vs. 18.8±2.5 s) occurring at early reperfusion. Additionally, fasting increased the concentration of beta-hydroxybutyrate and betahydroxybutyrate/acetoacetate ratio (87.8±27.0) compared to controls (7.9±1.7), reflecting altered mitochondrial redox state. It is concluded that three-day fasting effectively protected rat hearts against major endpoints of acute I/R injury. Further studies are needed to find out whether these beneficial effects can be linked to altered mitochondrial redox state resulting from increased ketogenesis., M. Šnorek ... [et al.]., and Obsahuje seznam literatury
It was previously shown that 4 hours´ lasting inhibition of nitric oxide synthesis by administration of an L-arginine analogue, the NG-nitro-L-arginine methyl ester (L-NAME) changed the affinity of the Na-binding site of Na,K-ATPase thus resulting in elevation of enzyme activity especially at higher concentrations of sodium. Using the same experimental model, we focused our attention in the present study to the question of binding of ATP to the enzyme molecule in the left ventricle (LV), ventricular septum (S) and the right ventricle (RV) of the dog heart. Activation of the enzyme by increasing concentrations of ATP revealed a significant increase of the Vmax only in septum (by 38 %). The KM increased significantly in septum (by 40 %) and in left ventricle (by 56 %) indicating an altered sensitivity of the ATP-binding site of Na,K-ATPase in the hearts of NO-deficient animals. The alterations of Na,K-ATPase in its ability to bind and hydrolyze ATP are localized to the tissue surrounding the cavity of the left ventricle., N. Vrbjar, M. Strnisková, O. Pecháňová, M. Gerová., and Obsahuje bibliografii
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