Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: CAS:74-79-3 (arginine)
 96,211 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The signal transduction pathway for vasorelaxation induced by human alpha-calcitonin gene-related peptide (human alpha-CGRP) was studied in rat thoracic aortic rings preconstricted with noradrenaline (10(-7) M). 2. Vasorelaxation by human alpha-CGRP was inhibited by haemoglobin (10(-6) M) and methylene blue (10(-5) M) but was unaffected by ibuprofen (10(-5) M). 3. Acetylcholine caused a 16 fold increase in levels of guanosine 3':5'-cyclic monophosphate (cyclic GMP) with levels of adenosine 3':5'-cyclic monophosphate (cyclic AMP) being unaltered. Human alpha-CGRP caused a 12 fold increase in levels of cyclic GMP but, in contrast to acetylcholine, evoked a 2.5 fold rise in levels of cyclic AMP. The rises in cyclic nucleotides evoked by human alpha-CGRP and acetylcholine were dependent on the presence of an intact endothelium. 4. NG-nitro-L-arginine (L-NOARG: 10(-5) M), which inhibits nitric oxide synthetase, inhibited the relaxant response to human alpha-CGRP and cyclic GMP accumulation without affecting the cyclic AMP accumulation. 5. The data presented in this paper suggests that human alpha-CGRP relaxes the rat thoracic aorta by releasing nitric oxide and stimulating guanylate cyclase. The stimulation of adenylate cyclase by human alpha-CGRP probably precedes the activation of nitric oxide synthase but could be unrelated to the relaxant response.
 ...
PMID:Human alpha-calcitonin gene-related peptide stimulates adenylate cyclase and guanylate cyclase and relaxes rat thoracic aorta by releasing nitric oxide. 136 70

Inhibitory nonadrenergic noncholinergic (i-NANC) nerves are the only neural bronchodilator pathway in human airways. Possible candidates for the neurotransmitter include vasoactive intestinal peptide (VIP) and nitric oxide (NO) and purines such as ATP. We have investigated the potential role of these neurotransmitters. Phosphoramidon (10(-5) M) significantly potentiated relaxations to low doses of VIP with no effect on i-NANC responses. Relaxations induced by VIp were abolished with alpha-chymotrypsin (2 U/ml), but i-NANC responses were unaffected. Reactive blue 2 had no effect on i-NANC neural responses, indicating that endogenous ATP was not involved. The NO synthase inhibitor L-NG-nitroarginine methyl ester (L-NAME, 10(-4) M) produced a concentration-dependent inhibition of the i-NANC response, producing almost complete inhibition at every frequency studied (0.5-40 Hz), whereas L-NG-monomethyl arginine was effective only at low stimulation frequencies. The inhibitory effect of L-NAME was partially reversed by L- but not D-arginine, and D-NAME was without effect. These results suggest that in human tracheal segments the neural bronchodilator response is mediated by NO, and there is no functional evidence for implicating VIP in this response.
 ...
PMID:Inhibitory NANC nerves in human tracheal smooth muscle: a quest for the neurotransmitter. 136 24

The glutamate receptor agonist N-methyl-D-aspartate (NMDA) stimulated a rapid, extracellular Ca(2+)-dependent conversion of [3H]arginine to [3H]citrulline in primary cultures of cerebellar granule cells, indicating receptor-mediated activation of nitric oxide (NO) synthase. The NMDA-induced formation of [3H]citrulline reached a plateau within 10 min. Subsequent addition of unlabeled L-arginine resulted in the disappearance of 3H from the citrulline pool, indicating a persistent activation of NO synthase after NMDA receptor stimulation. Glutamate, NMDA, and kainate, but not quisqualate, stimulated both the conversion of [3H]arginine to [3H]citrulline and cyclic GMP accumulation in a dose-dependent manner. Glutamate and NMDA showed similar potencies for the stimulation of [3H]citrulline formation and cyclic GMP synthesis, respectively, whereas kainate was more potent at inducing cyclic GMP accumulation than at stimulating [3H]citrulline formation. Both the [3H]arginine to [3H]citrulline conversion and cyclic GMP synthesis stimulated by NMDA were inhibited by the NMDA receptor antagonist MK-801 and by the inhibitors of NO synthase, NG-monomethyl-L-arginine (MeArg) and NG-nitro-L-arginine (NOArg). However, MeArg, in contrast to NOArg, also potently inhibited [3H]arginine uptake. Kainate (300 microM) stimulated 45Ca2+ influx to the same extent as 100 microM NMDA, but stimulated [3H]citrulline formation to a much lesser extent, which suggests that NO synthase is localized in subcellular compartments where the Ca2+ concentration is regulated mainly by the NMDA receptor.
 ...
PMID:Glutamate receptor agonists stimulate nitric oxide synthase in primary cultures of cerebellar granule cells. 137 78

Treatment of mesangial cells with interleukin 1 beta (IL-1 beta) or tumour necrosis factor alpha (TNF alpha) has been shown to increase cGMP formation, most probably due to induction of nitric oxide synthase. Here we report that maximum stimulation of cGMP formation over a 24-h period required the presence of IL-1 beta or TNF alpha during the first 18 h of induction. N4-monomethyl-L-arginine (L-NMMA) was a potent inhibitor of cytokine-induced cGMP formation while N4-nitro-L-arginine (L-NNA) was less active. Formation of nitric oxide was detected in the cytosol of cytokine-treated mesangial cells by activation of purified soluble guanylate cyclase and was stimulated by tetrahydrobiopterin, but not by calcium calmodulin. Treatment of cells with IL-1 beta or TNF alpha markedly attenuated the contractile response to a subsequent challenge with angiotensin II. Furthermore, conditioned medium from IL-1 beta-treated cells increased cGMP in untreated control cells.
 ...
PMID:Interleukin 1 beta and tumour necrosis factor alpha induce a macrophage-type of nitric oxide synthase in rat renal mesangial cells. 137 Apr 9

L-arginine causes insulin release from pancreatic B cells. Data from three model systems support the hypothesis that L-arginine-derived nitrogen oxides (NOs) mediate insulin release stimulated by L-arginine in the presence of D-glucose and by the hypoglycemic drug tolbutamide. The formation of NO in pancreatic B cells was detected both chemically and by the NO-induced accumulation of guanosine 3',5'-monophosphate. NG-substituted L-arginine analogs inhibited the release of both insulin and NO. Protein immunoblot and histochemical analysis with antiserum to type I NO synthase suggest that the formation of NO in pancreatic B cells is catalyzed by an NADPH- (reduced form of nicotinamide adenine dinucleotide phosphate), Ca2+/calmodulin-dependent type I NO synthase of about 150 kilodaltons.
 ...
PMID:Insulin secretion from pancreatic B cells caused by L-arginine-derived nitrogen oxides. 145 35

Long-term potentiation is a long-lasting, use-dependent increase in the strength of synaptic connections. We investigated the role of nitric oxide (NO) in determining the duration of potentiation induced by high frequency stimulation of afferents in the CA1 region of the rat hippocampus. The calcium/calmodulin-dependent production of NO can be initiated by activation of excitatory amino acid receptors and results in increased levels of cGMP in target cells. Here we report that only a relatively short-term potentiation can be induced in the presence of nitro-L-arginine methyl ester (L-NAME), an NO synthase inhibitor. The effects of L-NAME on the duration of potentiation are partially reversed by coadministration of L-arginine, a precursor of neuronal NO, and by dibutyryl cGMP. Hemoglobin, which binds extracellular NO, also shortens the duration of stimulus-induced potentiation. The results suggest a role for NO in the maintenance of activity-dependent synaptic enhancements, possibly via the generation of cGMP.
 ...
PMID:The role of nitric oxide in hippocampal long-term potentiation. 137 Dec 16

L-Arginine-derived nitric oxide (NO) acts as an inter- and intra-cellular signal molecule in many mammalian tissues including brain, where it is formed by a flavin-containing Ca2+/calmodulin-requiring NO synthase with NADPH, tetrahydrobiopterin (H4biopterin) and molecular oxygen as cofactors. We found that purified brain NO synthase acted as a Ca2+/calmodulin-dependent NADPH:oxygen oxidoreductase, catalysing the formation of hydrogen peroxide at suboptimal concentrations of L-arginine or H4biopterin, which inhibited the hydrogen peroxide formation with half-maximal effects at 11 microM and 0.3 microM respectively. Half-maximal rates of L-citrulline formation were observed at closely similar concentrations of these compounds, indicating that the NO synthase-catalysed oxygen activation was coupled to the synthesis of L-citrulline and NO in the presence of L-arginine and H4biopterin. N omega-Nitro-L-arginine, its methyl ester and N omega-monomethyl-L-arginine inhibited the synthesis of L-citrulline from L-arginine (100 microM) with half-maximal effects at 0.74 microM, 2.8 microM and 15 microM respectively. The N omega-nitro compounds also blocked the substrate-independent generation of hydrogen peroxide, whereas N omega-monomethyl-L-arginine did not affect this reaction. According to these results, activation of brain NO synthase by Ca2+ at subphysiological levels of intracellular L-arginine or H4biopterin may result in the formation of reactive oxygen species instead of NO, and N omega-nitro-substituted L-arginine analogues represent useful tools to effectively block NO synthase-catalysed oxygen activation.
 ...
PMID:Ca2+/calmodulin-dependent formation of hydrogen peroxide by brain nitric oxide synthase. 137 84

The ability of various compounds to stimulate cyclic GMP accumulation was studied in neuronal and astrocyte-enriched primary cultures from rat cerebrum. Glutamate was the only agonist eliciting a response in neurons whereas several agonists had an effect in astrocytes but only those due to norepinephrine and glutamate were of considerable magnitude. The responses were markedly inhibited by the nitric oxide synthase inhibitor NG-monomethyl-L-arginine. The effect of glutamate appears to be mediated predominantly by NMDA receptors in neurons and by quisqualate AMPA-insensitive receptors in astrocytes.
 ...
PMID:Different receptors mediate stimulation of nitric oxide-dependent cyclic GMP formation in neurons and astrocytes in culture. 137 80

The NADPH-diaphorase histochemical technique provides a simple and robust method to stain select populations of neurons throughout the brain. We have recently identified the enzyme responsible for this histochemical reaction to be nitric oxide synthase. This enzyme is responsible for the calcium-dependent synthesis of nitric oxide from arginine. Nitric oxide acts as a novel neural messenger by stimulating soluble guanylyl cyclase thereby increasing the levels of cyclic guanosine 3',5'-monophosphate in target cells. Thus the NADPH-diaphorase histochemical method allows the direct visualization of the neurons which use this novel signal transduction pathway. We now describe the detailed distribution of this enzyme in the rat brain. Our results suggest a widespread role for the nitric oxide-cyclic guanosine monophosphate system in the nervous system.
 ...
PMID:Histochemical mapping of nitric oxide synthase in the rat brain. 137 55

In primary cultures of astrocytes and granule cells from neonatal rat cerebellum, the activity and function of nitric oxide (NO) synthase were measured by the conversion of [3H]arginine to [3H]citrulline and the accumulation of cyclic guanosine monophosphate (cGMP), respectively. The glutamate receptor agonist N-methyl-D-aspartate (NMDA) and the Ca2+ ionophore A23187 stimulated NO synthase activity in cerebellar granule cells but not in astrocytes. In granule cells, NMDA, A23187, and sodium nitroprusside (SNP) elicited an accumulation of cGMP, whereas only SNP was active in astrocytes. However, in astrocytes that were incubated together with granule cells, NMDA induced a more than 3-fold increase in the concentration of cGMP; this increase was blocked by both the NO synthase inhibitor NG-monomethyl-L-arginine (MeArg) and the allosteric NMDA receptor antagonist (+)5-methyl-10,11-dihydro-5H-dibenzocyclohepten-5,10-imine maleate (MK-801). Thus, cerebellar astrocytes do not appear to express NO synthase but do contain guanylate cyclase, which can be activated by an NO-like factor produced by cerebellar granule cells after stimulation by NMDA.
 ...
PMID:In vitro interaction between cerebellar astrocytes and granule cells: a putative role for nitric oxide. 137 59


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>