Effect of Radiocontrast Agents on Intrarenal Nitric Oxide (NO) and NO Synthase Activity

1998 ◽  
Vol 6 (6) ◽  
pp. 557-562 ◽  
Author(s):  
Samuel N. Heyman ◽  
Marina Goldfarb ◽  
Fanni Carmeli ◽  
Ahuva Shina ◽  
Daniel Rahmilewitz ◽  
...  
2019 ◽  
Vol 72 (8) ◽  
pp. 1473-1476
Author(s):  
Nataliya Matolinets ◽  
Helen Sklyarova ◽  
Eugene Sklyarov ◽  
Andrii Netliukh

Introduction: Polytrauma patients have high risk of shock, septic complications and death during few years of follow-up. In recent years a lot of attention is paid to gaseous transmitters, among which are nitrogen oxide (NO) and hydrogen sulfide (H2S). It is known that the rise of NO and its metabolites levels occurs during the acute period of polytrauma. Nitric oxide and hydrogen sulfide are produced in different cell types, among which are lymphocytes. The aim: To investigate the levels of NO, NOS, iNOS, еNOS, H2S in lymphocytes lysate in patients at the moment of hospitalization and 24 hours after trauma. Materials and methods: We investigated the levels of NO, NO-synthase, inducible NO-synthase, endothelial NO-synthase, H2S in lymphocytes lysate in patients at the moment of hospitalization and 24 hours after trauma. Results: The study included 20 patients with polytrauma who were treated in the intensive care unit (ICU) of the Lviv Emergency Hospital. Tissue injury was associated with an increased production of NO, NOS, iNOS, еNOS during the acute period of polytrauma. At the same time, the level of H2S decreased by the end of the first day of traumatic injury. Conclusions: In acute period of polytrauma, significant increasing of iNOS and eNOS occurs with percentage prevalence of iNOS over eNOS on the background of H2S decreasing.


Author(s):  
I. A. Palagina

Succinate containing compounds possess many types of biological activity and are used for the development of drugs with the target and complex action. This paper is devoted to some aspects of the mechanism of succinamides’ action in a dose of 100 mg/kg. We studied the influence of the compound with antidiabetic properties, -phenylethylamide of 2-oxysuccinanyl acid ( -PhEA-OSAA), and its metabolites such as 2-hydroxyphenylsuccinamide (2-HPhSA) and β-phenylethylsuccinamide ( -PhESA) on the marker indicators of energetic metabolism (EM), antioxidant system (AOS) and nitric oxide (NO) metabolism in subacute experiment on rats. Studies have shown that the action of -FEA-OSAKA on metabolic homeostasis is realized through stimulation of EM, reduction of intensity of NO-synthase metabolism and weakening of the AOS. The nature of the action of -FES and 2-GFS, taking into account the indicators of the state of homeostasis, largely coincides with β-FEA-OSAKA. It was found that the key links in the mechanism of toxic action of succinamides are the effect on antioxidant potential, NO metabolism and energy processes.


1994 ◽  
Vol 267 (1) ◽  
pp. F190-F195 ◽  
Author(s):  
H. Tsukahara ◽  
Y. Krivenko ◽  
L. C. Moore ◽  
M. S. Goligorsky

It has been hypothesized that fluctuations of the ionic composition in the interstitium of juxtaglomerular apparatus (JGA) modulate the function of extraglomerular mesangial cells (MC), thereby participating in tubuloglomerular feedback (TGF) signal transmission. We examined the effects of isosmotic reductions in ambient sodium concentration ([Na+]) and [Cl-] on cytosolic calcium concentration ([Ca2+]i) in cultured rat MC. Rapid reduction of [Na+] or [Cl-] in the bath induced a concentration-dependent rise in [Ca2+]i. MC are much more sensitive to decreases in ambient [Cl-] than to [Na+]; a decrease in [Cl-] as small as 14 mM was sufficient to elicit a detectable [Ca2]i response. These observations suggest that MC can be readily stimulated by modest perturbations of extracellular [Cl-]. Next, we examined whether activation of MC by lowered ambient [Cl-] influences cellular nitric oxide (NO) production. Using an amperometric NO sensor, we found that a 13 mM decrease in ambient [Cl-] caused a rapid, Ca2+/calmodulin-dependent rise in NO release from MC. This response was not inhibitable by dexamethasone, indicating the involvement of the constitutive rather than the inducible type of NO synthase in MC. In addition, the NO release was blunted by indomethacin pretreatment, suggesting that a metabolite(s) of cyclooxygenase regulates the activation of NO synthase in MC. Our findings that small perturbations in external [Cl-] stimulate MC to release NO, a highly diffusible and rapidly acting vasodilator, provide a possible mechanism to explain the transmission of the signal for the TGF response within the JGA.


1994 ◽  
Vol 267 (1) ◽  
pp. R84-R88 ◽  
Author(s):  
M. Huang ◽  
M. L. Leblanc ◽  
R. L. Hester

The study tested the hypothesis that the increase in blood pressure and decrease in cardiac output after nitric oxide (NO) synthase inhibition with N omega-nitro-L-arginine methyl ester (L-NAME) was partially mediated by a neurogenic mechanism. Rats were anesthetized with Inactin (thiobutabarbital), and a control blood pressure was measured for 30 min. Cardiac output and tissue flows were measured with radioactive microspheres. All measurements of pressure and flows were made before and after NO synthase inhibition (20 mg/kg L-NAME) in a group of control animals and in a second group of animals in which the autonomic nervous system was blocked by 20 mg/kg hexamethonium. In this group of animals, an intravenous infusion of norepinephrine (20-140 ng/min) was used to maintain normal blood pressure. L-NAME treatment resulted in a significant increase in mean arterial pressure in both groups. L-NAME treatment decreased cardiac output approximately 50% in both the intact and autonomic blocked animals (P < 0.05). Autonomic blockade alone had no effect on tissue flows. L-NAME treatment caused a significant decrease in renal, hepatic artery, stomach, intestinal, and testicular blood flow in both groups. These results demonstrate that the increase in blood pressure and decreases in cardiac output and tissue flows after L-NAME treatment are not dependent on a neurogenic mechanism.


2004 ◽  
Vol 287 (1) ◽  
pp. L60-L68 ◽  
Author(s):  
Louis G. Chicoine ◽  
Michael L. Paffett ◽  
Tamara L. Young ◽  
Leif D. Nelin

Nitric oxide (NO) is produced by NO synthase (NOS) from l-arginine (l-Arg). Alternatively, l-Arg can be metabolized by arginase to produce l-ornithine and urea. Arginase (AR) exists in two isoforms, ARI and ARII. We hypothesized that inhibiting AR with l-valine (l-Val) would increase NO production in bovine pulmonary arterial endothelial cells (bPAEC). bPAEC were grown to confluence in either regular medium (EGM; control) or EGM with lipopolysaccharide and tumor necrosis factor-α (L/T) added. Treatment of bPAEC with L/T resulted in greater ARI protein expression and ARII mRNA expression than in control bPAEC. Addition of l-Val to the medium led to a concentration-dependent decrease in urea production and a concentration-dependent increase in NO production in both control and L/T-treated bPAEC. In a second set of experiments, control and L/T bPAEC were grown in EGM, EGM with 30 mM l-Val, EGM with 10 mM l-Arg, or EGM with both 10 mM l-Arg and 30 mM l-Val. In both control and L/T bPAEC, treatment with l-Val decreased urea production and increased NO production. Treatment with l-Arg increased both urea and NO production. The addition of the combination l-Arg and l-Val decreased urea production compared with the addition of l-Arg alone and increased NO production compared with l-Val alone. These data suggest that competition for intracellular l-Arg by AR may be involved in the regulation of NOS activity in control bPAEC and in response to L/T treatment.


1994 ◽  
Vol 87 (2) ◽  
pp. 179-186 ◽  
Author(s):  
H. Terence Cook ◽  
Alison J. Bune ◽  
Albertine S. Jansen ◽  
G. Michael Taylor ◽  
Rashpal K. Loi ◽  
...  

1. Endotoxin induces a shock-like syndrome with increased nitric oxide synthesis. To clarify the cellular source of NO in endotoxic shock we used immunohistochemistry and in situ hybridization to localize inducible NO synthase in rats given lipopolysaccharide or Corynebacterium parvum and lipopolysaccharide. Immunohistochemistry was carried out with an antibody raised against a synthetic peptide of mouse macrophage NO synthase. In situ hybridization was performed with 35S-labelled oligonucleotide probes corresponding to cDNA sequences common to mouse macrophage inducible NO synthase and rat vascular smooth inducible NO synthase. Monocytes and macrophages were identified by immunohistochemistry with the mouse monoclonal antibody ED1. 2. After lipopolysaccharide alone, the major site of NO synthase induction was monocytes and macrophages in multiple organs, principally liver and spleen. Bronchial, bile duct, intestinal and bladder epithelium and some hepatocytes also expressed inducible NO synthase. Expression peaked at 5 h and had returned to normal by 12 h except in spleen. 3. After priming with C. parvum, lipopolysaccharide led to a similar distribution of inducible NO synthase as lipopolysaccharide alone, but in addition there was more prominent hepatocyte staining, staining in macrophage granulomas in the liver and inducible NO synthase was present in some endothelial cells in the aorta. 4. These findings provide a direct demonstration of the cellular localization of inducible NO synthase after lipopolysaccharide.


1999 ◽  
Vol 6 (1) ◽  
pp. 63-76 ◽  
Author(s):  
Min Zhuo ◽  
Jarmo T. Laitinen ◽  
Xiao-Ching Li ◽  
Robert D. Hawkins

Perfusion of hippocampal slices with an inhibitor nitric oxide (NO) synthase blocked induction of long-term potentiation (LTP) produced by a one-train tetanus and significantly reduced LTP by a two-train tetanus, but only slightly reduced LTP by a four-train tetanus. Inhibitors of heme oxygenase, the synthetic enzyme for carbon monoxide (CO), significantly reduced LTP by either a two-train or four-train tetanus. These results suggest that NO and CO are both involved in LTP but may play somewhat different roles. One possibility is that NO serves a phasic, signaling role, whereas CO provides tonic, background stimulation. Another possibility is that NO and CO are phasically activated under somewhat different circumstances, perhaps involving different receptors and second messengers. Because NO is known to be activated by stimulation of NMDA receptors during tetanus, we investigated the possibility that CO might be activated by stimulation of metabotropic glutamate receptors (mGluRs). Consistent with this idea, long-lasting potentiation by the mGluR agonist tACPD was blocked by inhibitors of heme oxygenase but not NO synthase. Potentiation by tACPD was also blocked by inhibitors of soluble guanylyl cyclase (a target of both NO and CO) or cGMP-dependent protein kinase, and guanylyl cyclase was activated by tACPD in hippocampal slices. However, biochemical assays indicate that whereas heme oxygenase is constitutively active in hippocampus, it does not appear to be stimulated by either tetanus or tACPD. These results are most consistent with the possibility that constitutive (tonic) rather than stimulated (phasic) heme oxygenase activity is necessary for potentiation by tetanus or tACPD, and suggest that mGluR activation stimulates guanylyl cyclase phasically through some other pathway.


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