Little is known about the effect of chronic angiotensin-converting enzyme inhibition on the catecholamine levels in fowls. In this study, we investigated the effects of chronic lisinopri1 dihydrate (Ld) application on the plasma levels of adrenaline and noradrenaline and on the blood pressure. Lisinopril was given in different concentrations (25, 75 and 250 mg/l drinking water) to the white Leghorn chickens for 9 weeks, while the control group drank tap water only. Twenty-eight hours after the last lisinopril application, arterial blood pressure (BP), plasma adrenaline and noradrenaline levels, plasma renin (PRA) and plasma angiotensin-converting enzyme (ACE) activities were determined. In all concentrations, lisinopril significantly increased PRA and decreased ACE activities. Arterial BP was decreased only in the group receiving high lisinopril concentration (Controls 119±10.27, Ld3 98±5.4 mm Hg). However, the lower lisinopril concentrations did not alter arterial BP compared to the control group. Plasma noradrenaline levels were decreased in a concentration-dependent manner (47-58 %), but plasma adrenaline levels remained unchanged. The heart weight/body weight ratio was not changed in any of the lisinopril-treated groups. The persistent decrease in the blood pressure after lisinopril treatment was not directly related to a decrease of plasma ACE activity or plasma noradrenaline levels. Its mechanism still remains to be elucidated., H. S. Ozdemir, H. E. Aksulu, F. Karataş, B. Ustündag, I. Bingöl., and Obsahuje bibliografii
It has been suggested that thiazolidinediones (TZDs) ameliorate insulin resistance in muscle tissue by suppressing muscle lipid storage and the activity of novel protein kinase C (nPKC) isoforms. To test this hypothesis, we analyzed long-term metabolic effects of pioglitazone and the activation of nPKC-ε and -θ isoforms in an animal model of the metabolic syndrome, the spontaneously hypertensive rat (a congenic SHR strain with wild type Cd36 gene) fed a diet with 60 % sucrose from the age of 4 to 8 months. Compared to untreated controls, pioglitazone treatment was associated with significantly increased basal (809±36 vs 527±47 nmol glucose/g/2h, P<0.005) and insulinstimulated glycogenesis (1321±62 vs 749±60 nmol glucose/g/2h, P<0.0001) in isolated gastrocnemius muscles despite increased concentrations of muscle triglycerides (3.83±0.33 vs 2.25±0.12 μmol/g, P<0.005). Pioglitazone-treated rats exhibited significantly increased membrane/total (cytosolic plus membrane) ratio of both PKC-ε and PKC-θ isoforms compared to untreated controls. These results suggest that amelioration of insulin resistance after long-term pioglitazone treatment is associated with increased activation of PKC-ε and -θ isoforms in spite of increased lipid concentration in skeletal muscles., I. Marková ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
After global cerebral hypoxia, many patients are severely disabled even after intensive neurorehabilitation. Secondary mechanisms of brain injury as a result of biochemical and physiological events occur within a period of hours to months, and provide a window of opportunity for therapeutic intervention. Erythropoietin (EPO) has been shown to be neuroprotective in the brain subjected to a variety of injuries. Fifty-nine 3-month-old male Wistar rats were randomly distributed to experimental groups with respect to the housing (enriched environment – EE, standard housing – SH), to hypoxia exposure, and to EPO treatment. An acute mountain sickness model was used as a hypobaric hypoxia simulating an altitude of 8000 m. One half of the animals received erythropoietin injections, while the others were injected saline. Spatial memory was tested in a Morris water maze (MWM). The escape latency and the path length were measured. Better spatial learning in MWM was only seen in the group that received erythropoietin together with enriched environment. EPO administration itself had no influence on spatial memory. The results were very similar for both latencies and path lengths. These results support the idea that after brain injuries, the recovery can be potentiated by EPO administration combined with neurorehabilitation., M. Hralová, ... [et al.]., and Obsahuje seznam literatury
Advanced atherosclerotic changes can often resist even to very aggressive treatment. Although basic mechanisms of its origin and development are known, some important steps in this process are still waiting for more detailed explanation. Therefore, in addition to already proved aggressive lowering of LDL cholesterol, appropriate timing of atherosclerosis treatment is of the essence. Revealing different stages of atherosclerotic process, less or more sensitive to treatment is of primary importance; however, its detection is complicated by several facts including not exactly identifiable periods of quiescence and progression of atherosclerotic process. One of populations, study of which could add valuable information regarding this problem , are women in menop ausal transition. Previously unsuccessful therapy with hormone replacement therapy is restudied with focus on the time of/after menopause. Now, it is supposed to be favorable in women soon, approximately less than 8 years, after menopause. In addition, the same principle - optimal timing of the intervention of traditional cardiovascular risk factors, especially lipids, could be also of importance. Therefore, menopausal transition could be optimal period for the intervention in women at risk. However, this a pproach is to be proved by evidence from controlled prospective studies focused on lifestyle and/or pharmacological intervention., J. Piťha., and Obsahuje bibliografii
Domoic acid (DA) is a potent marine neurotoxine present in seafood. Intoxication by DA causes gastrointestinal symptoms like vomiting and diarrhoea and also the so-called amnesic shellfish poisoning (inflicting memory impairment and seizures). Since exposure to non-convulsive doses is relevant to the human health, we investigated the effect of low dose DA administration in adult Wistar rats. Rats were administered with DA at the dose 1.0 mg/kg and their behavior was monitored for one hour in three sessions. The first session started immediately after DA administration. The second and third session started one and two weeks later. After the third session, the histochemical analysis of the hippocampi of the animals was conducted (Fluoro-Jade B, bis-benzimide). DA increased time spent by locomotion and distance travelled in the second half of the first session and this effect was pronounced during the second and third session. Exploratory rearing was decreased by DA administration in the first half of the first session. DA influenced the grooming in biphasic manner (decrease followed by an increase of time spent by grooming). This biphasic trend was observed even two weeks after the DA administration. Histochemistry of DA treated rats did not confirm the presence of apoptotic bodies, Fluoro-Jade B positive cells were not found neither in CA1 nor CA3 area of the hippocampi. Our study revealed that a low dose of DA affect short and long-term the spontaneous behavior of rats without inducing neuronal damage., M. Schwarz, K. Jandová, I. Struk, D. Marešová, J. Pokorný, V. Riljak., and Obsahuje bibliografii
a1_The effect of low-salt diet on phospholipid composition and remodeling was examined in rat colon which represents a mineralocorticoid target tissue. To elucidate this question, male Wistar rats were fed a low-salt diet and drank distilled water (LS, low-salt group) or saline instead of water (HS, high-salt group) for 12 days before the phospholipid concentration and fatty acid composition of isolated colonocytes were examined. The dietary regimens significantly influenced the plasma concentration of aldosterone which was high in LS group and almost zero in HS group. Plasma concentration of corticosterone was unchanged. When expressed in terms of cellular protein content, a significantly higher concentration of phospholipids was found in LS group, with the exception of sphingomyelin (SM) and phosphatidylserine (PS). Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) accounted for more than 70 % of total phospholipids in both groups. A comparison of phospholipid distribution in LS and HS groups demonstrated a higher percentage of PE and a small, but significant, decrease of PC and SM in LS group. The percentage of phosphatidylinositol (PI), PS and cardiolipin (CL) were not affected by mineralocorticoid treatment. With respect to the major phospholipids (PE, PC), a higher level of n-6 polyunsaturated fatty acids (PUFA) and lower levels of monounsaturated fatty acids were detected in PC of LS group. The increase of PUFA predominantly reflected an increase in arachidonic acid by 53%. In comparison to the HS group, oleic acid content was decreased in PC and PE isolated from colonocytes of the LS group. Our data indicate that alterations in phospholipid concentration and metabolism can be detected in rats with secondary hyperaldosteronism., a2_The changes in phospholipid concentration and their fatty acid composition during fully developed effect of low dietary Na+ intake may reflect a physiologically important phenomenon with long-term consequences for membrane structure and function., L. Mrnka, O. Nováková, F. Novák, E. Tvrzická , J. Pácha., and Obsahuje bibliografii
Polyunsaturated omega-3 fatty acids ( ω-3 PUFA) are important components of cell membrane a ffecting its function and their deficiency is deleterious to health. We have previously shown that spontaneously hypertensive rats (SHR) are prone to life- threatening arrhythmias that are reduced by ω-3 PUFA intake. Purpose of this study was to explore plasma and red blood cells (RBC) profile of ω-3 and ω-6 PUFA as well as to determine ω-3 index, a risk factor for sudden cardiac death, in aged SHR and the effect of ω-3 PUFA intake. Male and female 12-month-old SHR and age-matched Wi star rats fed with ω-3 PUFA (200 mg/kg BW/day/2 month) were compared with untreated rats. Composition of ω-3 PUFA: alfa linolenic acid, eicosapentaenoic acid (EPA) and docosahexaen oic acid (DHA) as well as ω-6 PUFA: linoleic acid and arachidonic acid was analyzed by gas chromatography. Results showed sex- and strain-related differences of basal ω-3 and ω-6 PUFA levels in plasma and RBC as well as in response to ω-3 PUFA intake. Comparing to Wistar rats ω-3 index, expressed as a percentage of EPA+DHA of total fatty acids, was lower in SHR and it increased due to consumption of ω-3 PUFA. Findings support our hypothesis that lower ω-3 index may be also a marker of increased propensity of the hypertensive rat heart to malignant arrhythmias., B. Bačová ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Hypokalemia as a typical feature of primary aldosteronism (PA) is associated with muscle weakness and could contribute to lower cardio pulmonary fitness. The aim of this study was to describe cardiopulmonary fitness and exercise blood pressure and their determinants during a symptom-limited exercise stress test in patients with PA. We performed a cross-sectional study of patients with confirmed PA who were included before adrenal vein sampling on whom a symptom-limited exercise stress test with expired gas analysis was performed. Patients were switched to the treatment with doxazosin and verapamil at least tw o weeks befor e the study. In 27 patients (17 male) the VO 2peak was 25.4± 6.0 ml/k g/min which corresponds to 80.8 ±18.9 % of Czech national norm. Linear regression analysis shows that VO 2peak de pends on doxazosin dose (DX) (p=0.001) and kal emia (p= 0.02): VO 2peak = 4.2 - 1.0 * DX + 7.6 * Ka lemia. Patients with higher doxazosin doses had a longer history of hypertension and had used more antihypertensives before examination, thus indicating that VO 2peak also depends on the severity of hypertension. In patients with PA, lower cardiopulmonary fitness depends inversely on the severity of hypertension and o n lower plasma potassium level., V. Tuka, M. Matoulek, T. Zelinka, J. Rosa, O. Petrák, O. Mikeš, Z. Krátká, B. Štrauch, R. Holaj, J. Widimský Jr., and Obsahuje bibliografii
In this study we compared the levels of interleukin (IL)-6, IL-8, IL-10 and tumor necrosis factor-α (TNF-α) in population samples characterized by a high or low level of self-reported depression. We measured serum IL-6, IL-8, IL-10 and TNF-α in two cohorts which differed in scoring on the Zung Self-Rating Depression Scale (ZSDS). The group with a high score in ZSDS (average SDS index = 62.9) was called DEP (n=27), the group with a low score in ZSDS (average SDS index = 29.9) was called NDEP (n=16). The groups did not significantly differ in age, waist circumference and body mass index. For the assessment of serum cytokine levels multiplex immunoanalytic xMAP(LUMINEX) technology was used. We found lower IL-6 in the DEP group (medians; DEP 4.08 pg/ml vs. NDEP 6.11 pg/ml) on the border of statistical significance in multiple regression analysis (p=0.049). Serum levels of all other studied cytokines were not significantly different (medians; IL-8: DEP 2.18 pg/ml vs. NDEP 2.61 pg/ml; IL-10: DEP 2.85 pg/ml vs. NDEP 2.94 pg/ml; TNF-α: DEP 2.32 pg/ml vs. NDEP 2.30 pg/ml). These results are in contradiction to the prevailing opinion that proinflammatory cytokine levels are elevated in people with symptoms of depression. and Obsahuje bibliografii a bibliografické odkazy