Neurotransmitter substrate of spatial cognition belongs to current topics in behavioral neuroscience. The present study examined the effects of serotonin depletion with p-chlorophenylalanine on learning of rats in active place avoidance, a spatial task requiring allothetic mapping and cognitive coordination and highly dependent upon hippocampus. Serotonin depletion transiently increased locomotor activity in response to footshocks, but it did not change the avoidance efficiency measured by three spatial parameters. These results suggest that serotonin neurotransmission is not crucial for cognitive coordination and allothetic learning, i.e. the processes, which are crucial for active place avoidance performance., T. Petrásek, A. Stuchlík., and Obsahuje seznam literatury
Recent studies have demonstrated that adipocyte fatty acid binding proteins (FABP) may play a role in the etiopathogenesis of insulin resistance. The aim of our study was to assess serum FABP levels in obese patients with type 2 diabetes mellitus (T2DM) before and after 3 months of treatment with PPAR-α agonist fenofibrate (F) and to explore the relationship of FABP to biochemical parameters and measures of insulin sensitivity assessed by hyperinsulinemic-isoglycemic clamp. We measured biochemical parameters by standard laboratory methods, insulin sensitivity by hyperinsulinemic-isoglycemic clamp and serum concentrations of FABP by commercial ELISA kit in 11 obese females with T2DM before and after three months of treatment with PPAR-α agonist fenofibrate and in 10 lean healthy control women (C). Serum FABP levels were 2.5-fold higher in T2DM group relative to C and were not affected by fenofibrate treatment (C: 20.6±2.1 μg/l, T2DM before F: 55.6±5.7 μg/l, T2DM after F: 54.2±5.4 μg/l, p<0.0001 for C vs. T2DM before F). Hyperinsulinemia during the clamp significantly suppressed FABP levels in both C and T2DM group. FABP levels positively correlated with BMI, triglyceride levels, blood glucose, glycated hemoglobin, atherogenic index and insulin levels. An inverse relationship was found between FABP and HDL levels, metabolic clearance rate of glucose, M/I and MCRglc/I sensitivity indexes. We conclude that FABP levels are closely related to BMI, parameters of insulin sensitivity, HDL levels and measures of diabetes compensation. This combination makes FABP a valuable marker of metabolic disturbances in patients with type 2 diabetes mellitus., M. M. Haluzík ... [et al.]., and Obsahuje seznam literatury
Visfatin is an adipose tissue-derived hormone shown to correlate with visceral fat mass in patients with obesity. Its possible role in patients with different types of eating disorders is unknown. We measured fasting serum levels of visfatin and leptin and surrogate measures of insulin sensitivity in 10 untreated patients with anorexia nervosa (AN), 10 untreated patients with bulimia nervosa (BN) and 20 age-matched healthy women (C) to study the possible role of visfatin in these disorders. Patients with AN had severely decreased body mass index (BMI) and body fat content. BMI of BN group did not significantly differ from that of C group, whereas body fat content of BN group was significantly lower compared to C and higher compared to AN group, respectively. Serum glucose levels did not significantly differ among the groups studied, whereas serum insulin and leptin levels and HOMA index were significantly decreased in AN group relative to both C and BN group. In contrast, serum visfatin levels in both patients with AN and BN did not differ from those of C group. We conclude that circulating visfatin levels are not affected by the presence of chronic malnutrition in AN or binge/purge eating behavior in BN., I. Dostálová ...[et al.]., and Obsahuje seznam literatury
The aim of the study was to evaluate serum α-glutathione S-transferase (s-GSTA) levels in patients with cystic fibrosis (CF) and to compare s-GSTA with other liver function tests and with a hepatic ultrasound scan (US). The cytosolic enzyme, a-glutathione S-transferase is predominantly found in the liver and is distributed uniformly in the liver tissue. In our study s-GSTA levels were measured in 37 CF patients aged 1 to 28 years (mean age 10.4 years, 24 males). The control group consisted of 27 patients aged 2 to 17 years (mean age 8.5 years, 18 males). The presence of hepatobiliary abnormalities was assessed by clinical examination, ultrasound scan, s-GSTA, and conventional liver enzymes: alanine aminotransferase (ALT), alkaline phosphatase (ALP), aspartate aminotransferase (AST) and g-glutamyl transferase (GMT). The calculated 5-95 % range of s-GSTA for the control group was 0.098-2.54 mg/l, for the CF group 0.43-9.76 mg/l. Mean s-GSTA level in the control group was 1.55 mg/l (S.D.=1.57), and 2.05 mg/l (S.D.=2.60) in the CF group. In the group of CF patients, the serum levels were significantly higher than in the control group (P<0.01). No significant correlation existed in the CF group between s-GSTA and conventional liver tests (ALT, AST, ALP and GMT). Four patients in the CF group had hepatobiliary abnormalities detectable by conventional liver tests, s-GSTA and US. Four patients had abnormal s-GSTA, while conventional liver tests and US were normal. One other patient had abnormal hepatic US, but normal standard liver tests and s-GSTA. The study has suggested that a raised s-GSTA level might be a marker of possible pathological changes of the hepatobiliar system in CF patients. Serum GSTA seems to be a more sensitive marker than transaminases for the monitoring of hepatocellular integrity and as an early predictor of hepatic damage., K. Šídlová, V. Skalická, K. Kotaška, M. Pechová, M. Chada, J. Bartošová , Z. Hříbal, J. Nevoral, V. Vávrová, R. Průša., and Obsahuje bibliografii
We have studied natural killer (NK) activity, lymphoproliferative response, the release of several cytokines (IL-2, TNFa and IL-1b) and the ROS production in peritoneal leukocytes obtained 0, 2, 4, 12 and 24 h after lipopolysaccharide (LPS) injection. Lethal septic shock (100 % mortality occurred at 30 h after LPS administration) was caused in female BALB/c mice by intraperitoneal injection of 100 mg/kg of E. coli LPS. Cytotoxicity and lymphoproliferation assay were preformed together with the measurement of IL-1b, IL-2 and TNFa production, and quantification of ROS. Natural killer activity, spontaneous lymphoproliferative response, IL-2, TNFa, IL-b release and ROS production were increased after LPS injection. In conclusions, ROS and proinflammatory mediators produced by immune cells in response to LPS are involved in the oxidative stress of endotoxic shock. This oxidative state alters some functional characteristics of leukocytes (proliferation and NK activity)., V. M. Víctor, M. De la Fuente., and Obsahuje bibliografii
To determine whether a short-term change in dietary habits affects postprandial lipemia in men and women in the same way, postprandial triglyceridemia was measured in age- and BMI-matched young healthy men and women after two weeks on the self-selected low-fat low-cholesterol (LF) diet and after another two weeks on the self-selected high-fat high-cholesterol (HF) diet. After a standardized challenge meal (1.4 g fat/kg of body weight), men had higher postprandial triglyceridemia than women on the HF diet but no such difference was observed on the LF diet. The results of this preliminary study suggest that there may be important sex differences in the mechanisms regulating the postprandial lipemia response to different diets, women being able to adapt better to the HF diet with respect to postprandial lipemia., J. Kovář, R. Poledne., and Obsahuje bibliografii
In our previous study, healthy volunteers showed considerable short-term dynamics and patterns of the coherence of high time resolution between respiratory movements (RESP), heart rate fluctuations (HRF), and arterial blood pressure fluctuations (BPF). These are physiological indicators of autonomic short-term coordination mediated mainly by the brainstem which could be impaired in severe brain disorders. We hypothesized a direct or indirect impairment of these functions by these disorders and examined these patterns in 16 patients suffering from severe brain disorders. We calculated partial and ordinary coherence sequences and found almost the same patterns of coherence sequences as in healthy volunteers, but a distinctly reduced frequency of pattern incidence in patients (2.8*1.5/10 min/patient and 9.5*2.8/10 min/subject, P<0.05). Furthermore, there is a significantly smaller frequency of HRF-related patterns in patients with poor outcome, compared with those in patients with good outcome (1.8*0.8/10 min/patient and 4.5*2.7/10 min/patient, P<0.05). We conclude that severe brain disorders reduce physiological short-term dynamics of autonomic coordination patterns in the mean values of patients, but not in every patient., U. Zwiener, Ch. Schelenz, S. Bramer, D. Hoyer., and Obsahuje bibliografii
The possible linear short-term coordination between respiratory movements (RESP), heart rate fluctuations (HRF), and arterial blood pressure fluctuations (BPF) in conscious human beings has not yet been investigated because of the restricted time resolution of conventional time series analysis. At present, this short-term dynamics as an expression of relative coordination can be quantified by newly developed adaptive autoregressive modeling of time series using Kalman filtering. Thus, in 6 conscious healthy volunteers, RESP, HRF, and BPF were recorded during 10 min in the supine position, at rest and during paced breathing. A considerable part of calculated ordinary and partial coherence sequences of short-term resolution between RESP and HRF, RESP and BPF, and partially between HRF and BPF showed patterns varying in time that could be correlated to changes between gradual coordinations (coherence changing between 0.40 and 0.95). They were more seldom complete or absent. There were mostly opposite changes between partial coherence sequences RESP-HRF/BPF and RESP-BPF/HRF demonstrating competitive behavior between these coordinations. Paced breathing did not essentially affect any observed characteristics. Therefore, these coherence dynamics are not essentially dependent on voluntary breathing movements. We conclude that to a different extent these linear and changing couplings between RESP, HRF, and BPF in conscious human beings exhibit properties of short-term complete and more frequently gradual coordinations showing dynamics that can not be determined by conventional methods., U. Zwiener, C. Schelenz, S. Bramer, D. Hoyer., and Obsahuje bibliografii
Adiponectin belongs to the group of biologically active substances secreted by adipocytes and referred to as adipokines. Disturbances in its secretion an d/or action are thought to be involved in the pathogenesis of some metabolic diseases. However, regulation of adiponectin secretion is poorly elucidated. In the present study, short-term regulation of adiponectin secretion in primary rat adipocytes was investigated. Isolated rat adipocytes were incubated in Krebs-Ringer buffer containing 5 mM glucose and insulin alone or in the combination with epinephrine, dibutyryl-cAMP, adenosine A 1 receptor antagonist (DPCPX), palmitate, 2-bromopalmitate or inhibitor of mitochondrial electron transport (rotenone). Adipocyte exposure for 2 h to insulin (1-100 nM) significantly increased secretion of adiponectin compared with secretion observed without insulin. Furthermore, secretion of adipon ectin from adipocytes incubated with glucose and insulin was reduced by 1 and 2 μ M epinephrine, but not by 0.25 and 0.5 μ M epinephrine. Under similar conditions, 1 and 2 mM dibutyryl-cAMP substantially diminished secretion of adiponectin, whereas 0.5 mM dibutyryl-cAMP was ineffective. Secretion of adiponectin was found to be effectively decreased by DPCPX. Moreover, ad ipocyte exposure to rotenone also resulted in a substantial diminution of secretory response of adipocytes incubated for 2 h with glucose and insulin. It was also demonstrated that palmitate an d 2-bromopalmitate (0.06-0.5 mM) failed to affect secretion of leptin. The obtained results indicated that in short-term regulation of adiponectin secretion, insulin and epinephrine exert the opposite effects. These effects appeared as early as after 2 h of exposure. Moreover, deprivation of energy or blockade of adenosine action substantially decreased secretion of adiponectin., T. Szkudelski, L. Nogowski, K. Szkudelska., and Obsahuje bibliografii a bibliografické odkazy