Search results for "Prague"
showing 10 items of 652 documents
Phosphodiesterase 10A in the Rat Pineal Gland: Localization, Daily and Seasonal Regulation of Expression and Influence on Signal Transduction
2010
The cyclic nucleotide phosphodiesterase 10A (PDE10A) is highly expressed in striatal spiny projection neurons and represents a therapeutic target for the treatment of psychotic symptoms. As reported previously [J Biol Chem 2009; 284:7606–7622], in this study PDE10A was seen to be additionally expressed in the pineal gland where the levels of PDE10A transcript display daily changes. As with the transcript, the amount of PDE10A protein was found to be under daily and seasonal regulation. The observed cyclicity in the amount of PDE10A mRNA persists under constant darkness, is blocked by constant light and is modulated by the lighting regime. It therefore appears to be driven by the master cloc…
Nitric oxide is formed in a subpopulation of rat pineal cells and acts as an intercellular messenger.
1998
In the rat pineal, formation of the second messenger cyclic GMP (cGMP) is under adrenergic control. Two important sequential steps mediate adrenergic signal transduction by cGMP, receptor-stimulated nitric oxide (NO) formation by the enzyme NO synthase I (NOS I), and NO-induced cGMP formation by the cytosolic enzyme guanylyl cyclase. With regard to the first step in cGMP transduction (i.e. NO formation) we found, by means of NOS I immunostaining and NADPH-diaphorase staining, that the presence of NOS I was restricted to a subpopulation of pineal cells, generally surrounded by NOS I-negative cells. Considering the fact that NO is able to permeate the cell membrane, the question arises whethe…
Tumor Oxygenation in Anemic Rats: Effects of Erythropoietin Treatment Versus Red Blood Cell Transfusion
1995
Anemia was induced in rats by the development of a hemorrhagic ascites. These animals also bore solid tumors (DS-sarcomas) on the hind foot dorsum. The effects of two methods for anemia correction on oxygenation in the solid tumors were compared in this study. Anemia was corrected either chronically by erythropoietin administration (1000 IU/kg) over 14 days (EPO) or acutely by transfusion with red blood cells (TR). Non-anemic and untreated anemic animals served as controls. Tumor oxygenation was determined in anesthetized animals using polarographic needle electrodes and pO2 histography. The reduction in hematocrit and hemoglobin content found in anemic animals could successfully be correct…
Glucocorticoids mediate reduction of epithelial acetylcholine content in the airways of rats and humans
1998
The cholinergic system in rat and human airways and the effects of glucocorticoids were investigated by assay of choline acetyltransferase activity, by high-pressure liquid chromatography measurement of acetylcholine, and by anti-choline acetyltransferase immunocyto-/histochemistry. Human bronchi were obtained at surgery from patients with lung cancer. Group 1 patients did not suffer from additional lung diseases and had not been treated with glucocorticoids. Group 2 patients, who suffered in addition to lung cancer from chronic obstructive bronchitis, had been treated for at least 6 weeks before surgery with four puffs of flusinolid daily. Isolated bronchial epithelial cells as well as int…
Chronic alcohol feeding induces biochemical, histological, and functional alterations in rat retina.
2008
Aims: Ethanol consumption originates a wide spectrum of disorders, including alteration of visual function. Oxidative stress is included among the mechanisms by which alcohol predisposes nervous tissue to injury. Retina, which is the neurosensorial eye tissue, is particularly sensitive to oxidative stress. Methods: In this study we analyze the effect of long-term alcohol consumption on oxidative stress parameters of the rat retina, and its correlation to retinal function, as well as to the expression of the antiapoptotic protein Bcl-2. We also study the protective effect of ebselen, a synthetic selenoorganic antioxidant. Results: Herein we show that ethanol has a toxic effect on rat retina …
Upregulation of Phospholipase D Expression and Activation in Ventricular Pressure-Overload Hypertrophy
2005
Evidence for a role of phospholipase D (PLD) in cellular proliferation and differentiation is accumulating. We studied PLD activity and expression in normal and hypertrophic rat and human hearts. In rat heart, abdominal aortic banding (constriction to 50% of original lumen) caused hypertrophy in the left ventricle (as shown by weight index and ANP expression) by about 15% after 30 days without histological evidence of fibrosis or signs of decompensation and in the right ventricle after 100 days. The hypertrophy was accompanied by small increases of basal PLD activity and strong potentiation of stimulated PLD activity caused by 4β-phorbol-12β,13α-dibutyrate (PDB) and by phenylephrine. The mR…
Infrequent co-existence of nitric oxide synthase and parvalbumin, calbindin and calretinin immunoreactivity in rat pontine neurons.
1995
Neurons in the laterodorsal tegmental nucleus (LDTg), ventrolateral dorsal tegmental nucleus (LDTgV), pedunculopontine tegmental nucleus (PPTg), lateral and medial parabrachial nuclei (LPB and MPB) were immunoreactive to brain nitric oxide synthase (NOS) or isoform I. Double-labeling experiments showed that very few NOS-containing neurons in the pons were immunoreactive to any of the three calcium-binding proteins: calbindin-D 28K (CB-IR), parvalbumin (PV-IR) and calretinin (CR-IR). These findings extend our previous observation in the neocortex and suggest that a population of central NOS-containing neurons can be neurochemically characterized as CB/CR/PV deficient.
In vitro tracheal hyperresponsiveness to muscarinic receptor stimulation by carbachol in a rat model of bleomycin-induced pulmonary fibrosis
2006
Summary 1 Bleomycin-induced lung injury is widely used as an experimental model to investigate the pathophysiology of pulmonary fibrosis but the alterations in the pharmacological responsiveness of airways isolated from bleomycin-exposed animals has been scarcely investigated. The aim of this study was to examine the in vitro tracheal responses to muscarinic receptor stimulation with carbachol in a rat bleomycin model. 2 Concentration–response curves to carbachol (10 nm to 0.1 mm) were obtained in tracheal rings isolated from Sprague–Dawley rats 14 days after endotracheal bleomycin or saline. The intracellular calcium signal in response to carbachol (10 μm) was measured by epifluorescence m…
Effects of levosimendan on hemodynamics, local cerebral blood flow, neuronal injury, and neuroinflammation after asphyctic cardiac arrest in rats.
2014
Despite advances in cardiac arrest treatment, high mortality and morbidity rates after successful cardiopulmonary resuscitation are still a major clinical relevant problem. The post cardiac arrest syndrome subsumes myocardial dysfunction, impaired microcirculation, systemic inflammatory response, and neurological impairment. The calcium-sensitizer levosimendan was able to improve myocardial function and initial resuscitation success after experimental cardiac arrest/cardiopulmonary resuscitation. We hypothesized that levosimendan exerts beneficial effects on cerebral blood flow, neuronal injury, neurological outcome, and inflammation 24 hours after experimental cardiac arrest/cardiopulmonar…
CXCR2 blockade impairs angiotensin II-induced CC chemokine synthesis and mononuclear leukocyte infiltration.
2007
Objective—Angiotensin II (Ang-II) and mononuclear leukocytes are involved in atherosclerosis. This study reports the inhibition of Ang-II–induced mononuclear cell recruitment by CXCR2 antagonism and the mechanisms involved.Methods and Results—Ang-II (1 nmol/L, i.p. in rats) induced CXC and CC chemokines, followed by neutrophil and mononuclear cell recruitment. Administration of the CXCR2 antagonist, SB-517785-M, inhibited the infiltration of both neutrophils (98%) and mononuclear cells (60%). SB-517785-M had no effect on the increase in CXC chemokine levels but reduced MCP-1, RANTES, and MIP-1α release by 66%, 63%, and 80%, respectively. Intravital microscopy showed that pretreatment with S…