Search results for "arginine"
showing 10 items of 389 documents
Molecular mechanisms of NET formation and degradation revealed by intravital imaging in the liver vasculature
2015
AbstractNeutrophil extracellular traps (NETs) composed of DNA decorated with histones and proteases trap and kill bacteria but also injure host tissue. Here we show that during a bloodstream infection with methicillin-resistant Staphylococcus aureus, the majority of bacteria are sequestered immediately by hepatic Kupffer cells, resulting in transient increases in liver enzymes, focal ischaemic areas and a robust neutrophil infiltration into the liver. The neutrophils release NETs into the liver vasculature, which remain anchored to the vascular wall via von Willebrand factor and reveal significant neutrophil elastase (NE) proteolytic activity. Importantly, DNase although very effective at D…
Elevated serum triiodothyronine and intellectual and motor disability with paroxysmal dyskinesia caused by a monocarboxylate transporter 8 gene mutat…
2008
Monocarboxylate transporter 8 (MCT8 or SLC16A2) is important for the neuronal uptake of triiodothyronine (T3) in its function as a specific and active transporter of thyroid hormones across the cell membrane, thus being essential for human brain development. We report on a German male with Allan-Herndon-Dudley syndrome presenting with severe intellectual and motor disability, paroxysmal dyskinesia combined with truncal muscular hypotonia, and peripheral muscular hypertonia at his current age of 9 years. Additionally, the patient has a lesion in the left putamen region revealed by magnetic resonance imaging and elevated serum T3 levels. The male appeared to have a hemizygous mutation (R271H)…
Nitric oxide-active compounds modulate the intensity of glutamate-evoked responses in the globus pallidus of the rat
2011
Abstract Aim The effects of local applied NO-active compounds on glutamate (GLU)-evoked responses were investigated in globus pallidus (GP) neurons. Main methods Extracellularly recorded single units from anesthetized rats were treated with GLU before and during the microiontophoretic application of S-nitrosoglutathione (SNOG), a NO donor, and Nω-nitro- l -arginine methyl ester (L-NAME), a NOS inhibitor. Key findings Most GP cells were excited by SNOG whereas administration of L-NAME induced decrease of GP neurons activity. Nearly all neurons responding to SNOG and/or L-NAME showed significant modulation of their excitatory responses to the administration of iontophoretic GLU. In these cell…
Intensity of GABA-evoked responses is modified by nitric oxide-active compounds in the subthalamic nucleus of the rat: a microiontophoretic study.
2009
We have previously described modulatory effects of nitric oxide (NO)-active drugs on subthalamic nucleus (STN) neurons. In this study, the effects of microiontophoretically applied NO-active compounds on GABA-evoked responses were investigated in subthalamic neurons extracellularly recorded from anesthetized rats: 45 of 62 cells were excited by S-nitroso-glutathione (SNOG), an NO donor, whereas 28 of 43 neurons were inhibited by N-nitro-L-arginine methyl ester (L-NAME), a NOS inhibitor. Nearly all neurons responding to SNOG and/or L-NAME showed significant inhibitory responses to the administration of iontophoretic GABA. In these cells, the changes induced by NO-active drugs in the magnitud…
Critical role of nitric oxide on nicotine-induced hyperactivation of dopaminergic nigrostriatal system: electrophysiological and neurochemical eviden…
2010
Nicotine, the main psychoactive ingredient in tobacco, stimulates dopamine (DA) function, increasing DA neuronal activity and DA release. DA is involved in both motor control and in the rewarding and reinforcing effects of nicotine; however, the complete understanding of its molecular mechanisms is yet to be attained. Substantial evidence indicates that the reinforcing properties of drugs of abuse, including nicotine, can be affected by the nitric oxide (NO) system, which may act by modulating central dopaminergic function. In this study, using single cell recordings in vivo coupled with microiontophoresis and microdialysis in freely moving animals, the role of NO signaling on the hyperacti…
Spontaneous mechanical activity and evoked responses in isolated gastric preparations from normal and dystrophic (mdx) mice
2002
This study examined whether alterations of the spontaneous and evoked mechanical activity are present in the stomach of the mdx mouse, the animal model for Duchenne muscular dystrophy. The gastric mechanical activity from whole-organ of normal and mdx mice was recorded in vitro as changes of intraluminal pressure. All gastric preparations developed spontaneous tone and phasic contractions, although the tone of the mdx preparations was significantly greater. Atropine reduced the tone of the two preparations by the same degree. Nomega-nitro-l-arginine methyl ester (l-NAME) significantly increased the tone and spontaneous contractions only in the stomach from normal animals, but did not affect…
Effects Of COOH-terminal tripeptide alpha-MSH (11-13) on corneal epithelial wound healing:role of nitric oxide
2006
It is known that alpha-melanocyte stimulating hormone (alpha-MSH) may exert anti-inflammatory effects and facilitate reparative processes in different tissues. The effective message sequence of alpha-MSH resides in the COOH-terminal tripeptide alpha-MSH(11-13). This study was undertaken to investigate the effects of topical administration of the COOH-terminal tripeptide sequence of alpha-MSH (alpha-MSH(11-13), KPV) on corneal epithelial wound healing in rabbits and the possible role of nitric oxide (NO) in these effects. The whole corneal epithelium was denuded in both eyes by mechanical abrasion. The area of the corneal epithelial defect was stained with fluorescein, photographed, and then…
Nitrergic and purinergic interplay in inhibitory transmission in rat gastric fundus.
2007
Summary 1 This study was undertaken to analyse the involvement of ATP in non-adrenergic non- cholinergic (NANC) relaxation and possible interplay between nitrergic and purinergic systems in rat gastric fundus. 2 Experiments were performed in vitro on strips of longitudinal muscle from rat gastric fundus, recording the mechanical activity as changes in isometric force. In addition, NO release induced by different experimental conditions was assayed. 3 Under NANC conditions in serotonin-precontracted strips, electrical field stimulation (EFS) elicited a tetrodotoxin (TTX)-sensitive relaxation accompanied by nitric oxide (NO) release. This effect was antagonized by pretreatment with the NO …
Diabetes potentiates acetylcholine-induced relaxation in rabbit renal arteries.
2001
Abstract The response of rabbit renal arteries to acetylcholine and its endothelial modulation in diabetes were investigated. Acetylcholine induced concentration-related endothelium-dependent relaxation of renal arteries that was significantly more potent in diabetic rabbits than in control rabbits. Pretreatment with NG-nitro- l -arginine ( l -NOArg), indomethacin, or l -NOArg plus indomethacin induced partial inhibition of acetylcholine-induced relaxation. Inhibition induced by l -NOArg plus indomethacin was significantly higher in arteries from diabetic rabbits than in arteries from control rabbits. In renal arteries depolarised with KCl 30 mM and incubated with l -NOArg plus indomethacin…
Nitric oxide is involved in non-adrenergic, non-cholinergic inhibitory neurotransmission in rat duodenum
1995
1. In rat duodenum, electrical field stimulation (EFS) induced a relaxation due to activation of non-adrenergic, non-cholinergic (NANC) inhibitory intramural neurones. 2. Nitric oxide synthase (NOS) inhibitors, N omega-nitro-L-arginine (L-NNA) and N omega-nitro-L-arginine methyl ester (L-NAME), caused a dose-dependent reduction in amplitude of the NANC relaxation. Responses to low frequencies of stimulation were more sensitive to NOS inhibitors than those to high frequencies. 3. Effects induced by NOS inhibitors were stereospecific since D-NNA and D-NAME did not affect NANC relaxation. L-arginine, but not D-arginine, partially prevented the effects induced by NOS inhibitors on NANC relaxati…