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1722. Alterations in Calcium Homeostasis as Biological Marker for Mild Alzheimer´s Disease?
- Creator:
- Řípová, D., Platilová, V., Strunecká, A., Jirák, |R., and Höschl, C.
- Type:
- article, model:article, and TEXT
- Subject:
- Alzheimer's disease, Vascular dementia, Platelets, Calcium homeostasis, and Biological marker
- Language:
- English
- Description:
- The calcium hypothesis of neurodegenerative disorders such as Alzheimer´s disease (AD) suggests that altered cytosolic Ca2+ levels ([Ca2+]i) and/or disturbances in Ca2+ homeostasis concern cellular mechanisms underlying neuronal pathology. To search for a diagnostic marker of Alzheimer´s disease, we measured cytosolic calcium concentrations in platelets of AD patients, age-matched control subjects (AMC), and vascular dementia (VD) patients. The ([Ca2+]i) was determined using long wavelength indicator Fluo-3AM in 21 mild AD patients, 17 AMC, and 23 patients with VD. The basal values of [Ca2+]i were significantly lower in AD compared to AMC. After the addition of 1 mM calcium, the [Ca2+]i markedly increased in platelets of AD compared to AMC and VD. Measurement of calcium homeostasis could provide a very sensitive, but less specific biological marker of AD. These results support the hypothesis that influencing calcium homeostasis may provide a therapeutic strategy in dementia.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1723. Alterations in endothelin receptors following hemorrhage and resuscitation by centhaquin
- Creator:
- Briyal, S., Gandhakwala, R., Gulati, A., Lavhale, M. S., and Khan, M.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fyziologie člověka, human physiology, Hemorrhagic shock, Centhaquin, Resuscitation, Endothelin, Cytokines, 14, and 612
- Language:
- English
- Description:
- Endothelin-1 (ET-1) acts on ETA and ETB receptors and has been implicated in hemorrhagic shock (shock). We determined effect of shock and resuscitation by hypertonic saline (saline) or centhaquin on ETA and ETB receptor expression. Rats were anesthetized, a pressure catheter was placed in the left femoral artery; blood was withdrawn from the right femoral artery to bring mean arterial pressure (MAP) to 35 mm Hg for 30 min, resuscitation was performed and 90 min later sacrificed to collect samples for biochemical estimations. Resuscitation with centhaquin decreased blood lactate and increased MAP. Protein levels of ETA or ETB receptor were unaltered in the brain, heart, lung and liver following shock or resuscitation. In the abdominal aorta, shock produced an increase (140 %) in ETA expression which was attenuated by saline and centhaquin; ETB expression was unaltered following shock but was increased (79 %) by centhaquin. In renal medulla, ETA expression was unaltered following shock, but was decreased (-61 %) by centhaquin; shock produced a decrease (-34 %) in ETB expression which was completely attenuated by centhaquin and not saline. Shock induced changes in ETA and ETB receptors in the aorta and renal medulla are reversed by centhaquin and may be contributing to its efficacy., S. Briyal, R. Gandhakwala, M. Khan, M. S. Lavhale, A. Gulati., and Seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1724. Alterations in Hippocampal Antioxidant Enzyme Activities and Sympatho-Adrenomedullary System of Rats in Response to Different Stress Models
- Creator:
- Pajović, S.B., Pejić, S., Stojiljković, V., Gavrilović, Lj. , Dronjak, S., and Kanazir , D.T.
- Type:
- article, model:article, and TEXT
- Subject:
- Stress, Hippocampus, Antioxidant enzymes, and Catecholamines
- Language:
- English
- Description:
- The study deals with activity of three antioxidant enzymes, copper, zinc-superoxide dismutase (CuZnSOD), manganese superoxide dismutase (MnSOD), catalase (CAT) in hippocampus of rats, following the exposure to single chronic (individual housing or forced swimming) and acute (immobilization or cold) stress, as well as to combined chronic/acute stress. In addition, plasma noradrenaline (NA) and adrenaline (A) concentrations were measured in the same stress conditions, because their autooxidation can add to the oxidative stress. We observed that i) long-term social isolation and repeated forced swimming had minor effects on plasma catecholamines, but in the long-term pretreated groups, acute stressors caused profound elevation NA and A levels, ii) chronic stressors activate antioxidant enzymes, iii) acute stressors decrease catalase activity, their effects on CuZnSOD appear to be stressor-dependent, whereas MnSOD is not affected by acute stressors, and iv) pre-exposure to chronic stress affects the antioxidant-related effects of acute stressors, but this effect depends to a large extent on the type of the chronic stressor. Based on both metabolic and neuroendocrine data, long-term isolation appears to be a robust psychological stressor and to induce a “priming” effect specifically on the CuZnSOD and CAT activity.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1725. Alterations in the baroreceptor-heart rate reflex in conscious inbred polydipsic (STR/N) mice
- Creator:
- Chu, C. P., Cui, B. R., Kannan, H., and Qiu, D. L.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, physiology, phenylephrine, sodium nitroprusside, baroreceptor reflex, inbred polydipsic mice, 14, and 612
- Language:
- English
- Description:
- STR/N is an inbred strain of mice which is known to exhibit extreme polydipsia and polyuria. We previously found central administration of angiotensin II enhanced cardiovascular responses in STR/N mice than normal mice, suggesting that STR/N mice might exhibit different cardiovascular responses. Therefore, in this study, we investigated daily mean arterial blood pressure and heart rate, and changes in the baroreceptor-heart rate reflex in conscious STR/N mice and control (ICR) mice. We found that variability in daily mean arterial blood pressure and heart rate was significantly larger in STR/N mice than in ICR mice (p<0.05). There was a stronger response to phenylephrine (PE) in STR/N mice than in ICR mice. For baroreceptor reflex sensitivity, in the rapid response period, the slopes of PE and sodium nitroprusside (SNP) were more negative in STR/N mice than in ICR mice. In the later period, the slopes of PE and SNP were negatively correlated between heart rate and blood pressure in ICR mice, but their slopes were positively correlated in STR/N mice. These results indicated that STR/N mice exhibited the different cardiovascular responses than ICR mice, suggesting that the dysfunction of baroreceptor reflex happened in conscious STR/N mice., C. P. Chu, B. R. Cui, H. Kannan, D. L. Qiu., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1726. Alterations in the expression of the apurinic/apyrimidinic endonuclease-1/redox factor-1 (APE/ref-1) and DNA damage in the caudal region of acute and chronic spinal cord injured rats treated by embryonic neural stem cells
- Creator:
- Dagci, T., Armagan, G., Konyalioglu, S., and Yalcin, A.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, poranění míchy, spinal cord injuries, stem cell transplantation, DNA damage, APE protein, ref-1 protein, 14, and 612
- Language:
- English
- Description:
- The oxidative mechanisms of injury-induced damage of neurons within the spinal cord are not very well understood. We used a model of T8-T9 spinal cord injury (SCI) in the rat to induce neuronal degeneration. In this spinal cord injury model, unilateral avulsion of the spinal cord causes oxidative stress of neurons. We tested the hypothesis that apurinic/apyrimidinic endonuclease (or redox effector factor-1, APE/Ref-1) regulates this neuronal oxidation mechanism in the spinal cord region caudal to the lesion, and that DNA damage is an early upstream signal. The embryonic neural stem cell therapy significantly decreased DNA- damage levels in both study groups - acutely (followed up to 7 days after SCI), and chronically (followed up to 28 days after SCI) injured animals. Meanwhile, mRNA levels of APE/Ref-1 significantly increased after embryonic neural stem cell therapy in acutely and chronically injured an imals when compared to acute and chronic sham groups. Our da ta has demonstrated that an increase of APE/Ref-1 mRNA levels in the caudal region of spinal cord strongly correlated with DNA damage after traumatic spinal cord injury. We suggest that DNA damage can be observed both in lesional and caudal regions of the acutely and chronically injured groups, but DNA damage is reduced with embryonic neural stem cell therapy., T. Dagci, G. Armagan, S. Konyalioglu, A. Yalcin., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1727. Alterations of human immune system functions in relation to environmental contamination, gender and alcohol consumption intensity
- Creator:
- Kazbariene, Birute
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1728. Alterations of NO synthase isoforms in brain and kidney of rats with genetic and salt hypertension
- Creator:
- Silvie Hojná, Jaroslav Kuneš, and Jan Zicha
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, ledviny, kidneys, brainstem, diencephalon, NO synthase, genetic hypertension, 14, and 612
- Language:
- English
- Description:
- Both brain and peripheral nitric oxide (NO) play a role in the control of blood pressure and circ ulatory homeostasis. Central NO production seems to counteract angiotensin II-induced enhancement of sympathetic tone. The aim of our study was to evaluate NO synthase (NOS) activity and protein expression of its three isoforms - neuronal (nNOS), endothelial NOS (eNOS) and inducible (iNOS) - in two brain regions involved in blood pressure control (diencephalon and brainstem) as well as in the kidney of young adult rats with either genetic (12-week-old SHR) or salt- induced hypertension (8-week-old Dahl rats). We have demonstrated reduced nNOS and iNOS expression in brainstem of both hypertensive models. In SHR this abnormality was accompanied by attenuated NOS activity and was corrected by chronic captopril treatment which prevented the development of genetic hypertension. In salt hypertensive Dahl rats nNOS and iNOS expression was also decrea sed in the diencephalon where neural structures important for salt hypertension development are located. As far as peripheral NOS activity and expression is concerned, renal eNOS expression was considerably reduced in both genetic and salt-induced hypertension. In conclusions, we disclosed similar changes of NO system in the brainstem (but not in the diencephalon) of rats with genetic and salt-induced hypertension. Decreased nNOS ex pression was associated with increased blood pressure due to enhanced sympathetic tone., S. Hojná, J. Kuneš, J. Zicha., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1729. Altered Balance of Vasoactive Systems in Experimental Hypertension: The Role of Relative NO Deficiency
- Creator:
- Kuneš, J., Hojná, S., Kadlecová, M., Dobešová, Z., Rauchová, H., Vokurková, M., Loukotová, J., Pecháňová, O., and Zicha, J.
- Type:
- article, model:article, and TEXT
- Subject:
- Nitric oxide, Sympathetic nervous system, Reactive oxygen species, Vasoactive system balance, nifedipinesensitive BP component, and Calcium influx
- Language:
- English
- Description:
- This review summarizes our findings concerning the altered balance of vasoactive systems (namely sympathetic nervous system and nitric oxide) in various forms of experimental hypertension – genetic hypertension (SHR, HTG rats), salt hypertension (Dahl rats) and NO-deficient hypertension (L-NAME-treated rats). An attempt is made to define relative NO deficiency (compared to the existing level of sympathetic vasoconstriction), to describe its possible causes and to evaluate particular indicators of its extent. A special attention is paid to reactive oxygen species, their interaction with NO metabolism, cell Ca2+ handling and blood pressure regulation. Our current effort is focused on the investigation of abnormal regulation of cytosolic Ca2+ levels in smooth muscle and endothelium of hypertensive animals. Such a research should cl arify the mechanisms by which genetic and/or environmental factors could chronically modify blood pressure level.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1730. Altered blood-brain barrier permeability and its effect on the distribution of Evans blue and sodium fluorescein in the rat brain applied by intracarotid injection
- Creator:
- Petr Kozler and Pokorný, J.
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, hematoencefalická bariéra, fluorescenční mikroskopie, blood-brain barrier, fluorescence microscopy, cellular edema, intravital dyes, 14, and 612
- Language:
- English
- Description:
- The aim was to study the blood-brain permeability according to the distribution in the rat brain of Evans blue (EB) and sodium fluorescein (NaFl) administered by an intracarotid injection. Eighteen animals were divided into six groups according to the state of the blood-brain barrier (BBB) at the moment when the dyes were being applied. In the first two groups, the BBB was intact, in groups 3 and 4 the barrier had been opened osmotically prior to the application of the dyes, and in groups 5 and 6 a cellular edema was induced by hyperhydration before administration of the dyes. The intracellular and extracellular distribution of the dyes was studied by fluorescence microscopy. The histological picture thus represented the morphological correlate of the way BBB permeability had been changed before the application of the dyes., P. Kozler, J. Pokorný., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public