scholarly journals Nitric Oxide-Dependent Mechanisms Underlying MK-801- or Scopolamine-Induced Memory Dysfunction in Animals: Mechanistic Studies

2021 ◽  
Vol 22 (22) ◽  
pp. 12282
Author(s):  
Paulina Cieślik ◽  
Anna Siekierzycka ◽  
Adrianna Radulska ◽  
Agata Płoska ◽  
Grzegorz Burnat ◽  
...  

MK-801, an NMDA receptor antagonist, and scopolamine, a cholinergic receptor blocker, are widely used as tool compounds to induce learning and memory deficits in animal models to study schizophrenia or Alzheimer-type dementia (AD), respectively. Memory impairments are observed after either acute or chronic administration of either compound. The present experiments were performed to study the nitric oxide (NO)-related mechanisms underlying memory dysfunction induced by acute or chronic (14 days) administration of MK-801 (0.3 mg/kg, i.p.) or scopolamine (1 mg/kg, i.p.). The levels of L-arginine and its derivatives, L-citrulline, L-glutamate, L-glutamine and L-ornithine, were measured. The expression of constitutive nitric oxide synthases (cNOS), dimethylaminohydrolase (DDAH1) and protein arginine N-methyltransferases (PMRTs) 1 and 5 was evaluated, and the impact of the studied tool compounds on cGMP production and NMDA receptors was measured. The studies were performed in both the cortex and hippocampus of mice. S-nitrosylation of selected proteins, such as GLT-1, APP and tau, was also investigated. Our results indicate that the availability of L-arginine decreased after chronic administration of MK-801 or scopolamine, as both the amino acid itself as well as its level in proportion to its derivatives (SDMA and NMMA) were decreased. Additionally, among all three methylamines, SDMA was the most abundant in the brain (~70%). Administration of either compound impaired eNOS-derived NO production, increasing the monomer levels, and had no significant impact on nNOS. Both compounds elevated DDAH1 expression, and slight decreases in PMRT1 and PMRT5 in the cortex after scopolamine (acute) and MK-801 (chronic) administration were observed in the PFC, respectively. Administration of MK-801 induced a decrease in the cGMP level in the hippocampus, accompanied by decreased NMDA expression, while increased cGMP production and decreased NMDA receptor expression were observed after scopolamine administration. Chronic MK-801 and scopolamine administration affected S-nitrosylation of GLT-1 transport protein. Our results indicate that the analyzed tool compounds used in pharmacological models of schizophrenia or AD induce changes in NO-related pathways in the brain structures involved in cognition. To some extent, the changes resemble those observed in human samples.

2000 ◽  
Vol 279 (6) ◽  
pp. F1092-F1100 ◽  
Author(s):  
Jörg Schwöbel ◽  
Tina Fischer ◽  
Bettina Lanz ◽  
Markus Mohaupt

Angiotensin II (ANG II) and nitric oxide (NO) have contrasting vascular effects, yet both sustain inflammatory responses. We investigated the impact of ANG II on lipopolysaccharide (LPS)/interferon-γ (IFN)-induced NO production in cultured rat mesangial cells (MCs). LPS/IFN-induced nitrite production, the inducible form of nitric oxide synthase (NOS-2) mRNA, and protein expression were dose dependently inhibited by ANG II on coincubation, which was abolished on ANG II type 2 (AT2) receptor blockade by PD-123319. Homology-based RT-PCR verified the presence of AT1A, AT1B, and AT2 receptors. To shift the AT receptor expression toward the type 1 receptor, two sets of experiments were performed: LPS/IFN preincubation for 24 h was followed by 8-h coincubation with ANG II; or during 24-h coincubation of LPS/IFN and ANG II, dexamethasone was added for the last 6-h period. Both led to an amplified overall expression of NOS-2 protein and NO production that was inhibitable by actinomycin D in the first setup. Induced NO production was enhanced via the AT1 receptor; however, it was diminished via the AT2 receptor. In conclusion, induced NO production is negatively controlled by the AT2, whereas AT1 receptor stimulation enhanced NO synthesis in MCs. The overall NO availability depended on the onset of the inflammatory stimuli with respect to ANG II exposure and the available AT receptors.


1997 ◽  
Vol 17 (2) ◽  
pp. 153-160 ◽  
Author(s):  
Anish Bhardwaj ◽  
Frances J. Northington ◽  
Lee J. Martin ◽  
Daniel F. Hanley ◽  
Richard J. Traystman ◽  
...  

We tested the hypothesis that stimulation of metabotropic glutamate receptors (mGluRs) increases nitric oxide (NO) production in the hippocampus in vivo. Microdialysis probes were placed bilaterally into the CA3 region of the hippocampus of adult Sprague–Dawley rats under pentobarbital anesthesia. Probes were perfused for 5 h with artificial cerebrospinal fluid (CSF) containing 3 μM [14C]-L-arginine. Recovery of [14C]-L-citrulline in the effluent was used as a marker of NO production. In nine groups of rats, increases in [14C]-L-citrulline recovery were compared between right- and left-sided probes perfused with various combinations of the selective mGluR agonist, trans-(1 S,3 R)-1-amino-1,3-cyclopentanedicarboxylic acid (ACPD); the mGluR antagonist, (±)- α-methyl-4-carboxyphenylglycine (MCPG); the NO synthase inhibitor, N-nitro-L-arginine (LNNA); the ryanodine sensitive calcium-release channel inhibitor dantrolene, the non- N-methyl-D-aspartate (NMDA); receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX); the NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-5 H-dibenzo[ a,d] cyclohepten-5,10-imine (MK-801); and the Na+ channel blocker, tetrodotoxin. Recovery of [14C]-L-citrulline during perfusion with artificial CSF progressively increased to 90 ± 21 fmol/min (± SD) over 5 h. Perfusion in the contralateral hippocampus with 1 m M ACPD augmented [14C]-L-citrulline recovery to 250 ± 81 fmol/min. Perfusion of 1 m M nitroarginine + ACPD inhibited [14C]-L-citrulline recovery compared to that with ACPD alone. Perfusion with 1 m M MCPG + ACPD attenuated ACPD enhanced [14C]-L-citrulline recovery. Perfusion of 1 m M dantrolene + ACPD inhibited the ACPD-evoked increase in [14C]-L-citrulline recovery. Perfusion of 1 m M MCPG or dantrolene without ACPD did not decrease [14C]-L-citrulline recovery as compared to CSF alone. ACPD-enhanced [14C]-L-citrulline recovery was not attenuated by CNQX, MK-801, or tetrodotoxin (TTX). Using an indirect method of assessing NO production in vivo, these data demonstrate that mGluR stimulation enhances NO production in rat hippocampus. Inhibition with dantrolene suggests that calcium-induced calcium release amplifies the inositol triphosphate-mediated calcium signal associated with mGluR stimulation, thereby resulting in augmented calcium-dependent NO production.


2007 ◽  
Vol 103 (5) ◽  
pp. 1506-1512 ◽  
Author(s):  
R. El Hasnaoui-Saadani ◽  
R. Cardenas Alayza ◽  
T. Launay ◽  
A. Pichon ◽  
P. Quidu ◽  
...  

The objective of our study was to assess the role of neuronal nitric oxide synthase (nNOS) in the ventilatory acclimatization to hypoxia. We measured the ventilation in acclimatized Bl6/CBA mice breathing 21% and 8% oxygen, used a nNOS inhibitor, and assessed the expression of N-methyl-d-aspartate (NMDA) glutamate receptor and nNOS (mRNA and protein). Two groups of Bl6/CBA mice ( n = 60) were exposed during 2 wk either to hypoxia [barometric pressure (PB) = 420 mmHg] or normoxia (PB = 760 mmHg). At the end of exposure the medulla was removed to measure the concentration of nitric oxide (NO) metabolites, the expression of NMDA-NR1 receptor, and nNOS by real-time RT-PCR and Western blot. We also measured the ventilatory response [fraction of inspired O2 (FiO2) = 0.21 and 0.08] before and after S-methyl-l-thiocitrulline treatment (SMTC, nNOS inhibitor, 10 mg/kg ip). Chronic hypoxia caused an increase in ventilation that was reduced after SMTC treatment mainly through a decrease in tidal volume (Vt) in normoxia and in acute hypoxia. However, the difference observed in the magnitude of acute hypoxic ventilatory response [minute ventilation (V̇e) 8% − V̇e 21%] in acclimatized mice was not different. Acclimatization to hypoxia induced a rise in NMDA receptor as well as in nNOS and NO production. In conclusion, our study provides evidence that activation of nNOS is involved in the ventilatory acclimatization to hypoxia in mice but not in the hypoxic ventilatory response (HVR) while the increased expression of NMDA receptor expression in the medulla of chronically hypoxic mice plays a role in acute HVR. These results are therefore consistent with central nervous system plasticity, partially involved in ventilatory acclimatization to hypoxia through nNOS.


2000 ◽  
Vol 88 (4) ◽  
pp. 1381-1389 ◽  
Author(s):  
Ivan T. Demchenko ◽  
Albert E. Boso ◽  
Thomas J. O'Neill ◽  
Peter B. Bennett ◽  
Claude A. Piantadosi

We have tested the hypothesis that cerebral nitric oxide (NO) production is involved in hyperbaric O2 (HBO2) neurotoxicity. Regional cerebral blood flow (rCBF) and electroencephalogram (EEG) were measured in anesthetized rats during O2 exposure to 1, 3, 4, and 5 ATA with or without administration of the NO synthase inhibitor ( N ω-nitro-l-arginine methyl ester), l-arginine, NO donors, or the N-methyl-d-aspartate receptor inhibitor MK-801. After 30 min of O2 exposure at 3 and 4 ATA, rCBF decreased by 26–39% and by 37–43%, respectively, and was sustained for 75 min. At 5 ATA, rCBF decreased over 30 min in the substantia nigra by one-third but, thereafter, gradually returned to preexposure levels, preceding the onset of EEG spiking activity. Rats pretreated with N ω-nitro-l-arginine methyl ester and exposed to HBO2 at 5 ATA maintained a low rCBF. MK-801 did not alter the cerebrovascular responses to HBO2at 5 ATA but prevented the EEG spikes. NO donors increased rCBF in control rats but were ineffective during HBO2 exposures. The data provide evidence that relative lack of NO activity contributes to decreased rCBF under HBO2, but, as exposure time is prolonged, NO production increases and augments rCBF in anticipation of neuronal excitation.


2021 ◽  
Author(s):  
Anuj K Yadav ◽  
Michael C. Lee ◽  
Melissa Lucero ◽  
Christopher J. Reinhardt ◽  
ShengZhang Su ◽  
...  

<p>Nitric oxide (NO) plays a critical role in acute and chronic inflammation. NO’s contributions to cancer are of particular interest due to its context-dependent bioactivities. For example, immune cells initially produce cytotoxic quantities of NO in response to the nascent tumor. However, it is believed that this fades over time and reaches a concentration that supports the tumor microenvironment (TME). These complex dynamics are further complicated by other factors, such as diet and oxygenation, making it challenging to establish a complete picture of NO’s impact on tumor progression. Although many activity-based sensing (ABS) probes for NO have been developed, only a small fraction have been employed <i>in vivo </i>and fewer yet are practical in cancer models where the NO concentration is < 200 nM. To overcome this outstanding challenge, we have developed BL<sub>660</sub>-NO, the first ABS probe for NIR bioluminescence imaging of NO in cancer. Owing to the low intrinsic background, high sensitivity, and deep tissue imaging capabilities of our design, BL<sub>660</sub>-NO was successfully employed to visualize endogenous NO in cellular systems, a human liver metastasis model, and a murine breast cancer model. Importantly, its exceptional performance facilitated the design of a dietary study to examine the impact of NO on the TME by varying the intake of fat. BL<sub>660</sub>-NO provides the first direct molecular evidence that intratumoral NO becomes elevated in mice fed a high-fat diet who became obese with larger tumors compared to control animals on a low-fat diet. These results indicate that an inflammatory diet can increase NO production via recruitment of macrophages and overexpression of iNOS which in turn can drive tumor progression.<br></p>


2006 ◽  
Vol 72 (3) ◽  
pp. 2200-2205 ◽  
Author(s):  
Peter S. Choi ◽  
Zeki Naal ◽  
Charles Moore ◽  
Emerilis Casado-Rivera ◽  
Hector D. Abruña ◽  
...  

ABSTRACT A series of experiments was undertaken to learn more about the impact on other bacteria of nitric oxide (NO) produced during denitrification. The denitrifier Rhodobacter sphaeroides 2.4.3 was chosen as a denitrifier for these experiments. To learn more about NO production by this bacterium, NO levels during denitrification were measured by using differential mass spectrometry. This revealed that NO levels produced during nitrate respiration by this bacterium were in the low μM range. This concentration of NO is higher than that previously measured in denitrifiers, including Achromobacter cycloclastes and Paracoccus denitrificans. Therefore, both 2.4.3 and A. cycloclastes were used in this work to compare the effects of various NO levels on nondenitrifying bacteria. By use of bacterial overlays, it was found that the NO generated by A. cycloclastes and 2.4.3 cells during denitrification inhibited the growth of both Bacillus subtilis and R. sphaeroides 2.4.1 but that R. sphaeroides 2.4.3 caused larger zones of inhibition in the overlays than A. cycloclastes. Both R. sphaeroides 2.4.3 and A. cycloclastes induced the expression of the NO stress response gene hmp in B. subtilis. Taken together, these results indicate that there is variability in the NO concentrations produced by denitrifiers, but, irrespective of the NO levels produced, microbes in the surrounding environment were responsive to the NO produced during denitrification.


2019 ◽  
Vol 20 (13) ◽  
pp. 3273 ◽  
Author(s):  
Zdenka Kristofikova ◽  
Jana Sirova ◽  
Jan Klaschka ◽  
Saak V. Ovsepian

Aging and chronic sleep deprivation (SD) are well-recognized risk factors for Alzheimer’s disease (AD), with N-methyl-D-aspartate receptor (NMDA) and downstream nitric oxide (NO) signalling implicated in the process. Herein, we investigate the impact of the age- and acute or chronic SD-dependent changes on the expression of NMDA receptor subunits (NR1, NR2A, and NR2B) and on the activities of NO synthase (NOS) isoforms in the cortex of Wistar rats, with reference to cerebral lateralization. In young adult controls, somewhat lateralized seasonal variations in neuronal and endothelial NOS have been observed. In aged rats, overall decreases in NR1, NR2A, and NR2B expression and reduction in neuronal and endothelial NOS activities were found. The age-dependent changes in NR1 and NR2B significantly correlated with neuronal NOS in both hemispheres. Changes evoked by chronic SD (dysfunction of endothelial NOS and the increasing role of NR2A) differed from those evoked by acute SD (increase in inducible NOS in the right side). Collectively, these results demonstrate age-dependent regulation of the level of NMDA receptor subunits and downstream NOS isoforms throughout the rat brain, which could be partly mimicked by SD. As described herein, age and SD alterations in the prevalence of NMDA receptors and NOS could contribute towards cognitive decline in the elderly, as well as in the pathobiology of AD and the neurodegenerative process.


2001 ◽  
Vol 280 (3) ◽  
pp. R771-R779 ◽  
Author(s):  
José M. Valdivielso ◽  
Carlos Crespo ◽  
José R. Alonso ◽  
Carlos Martı́nez-Salgado ◽  
Nelida Eleno ◽  
...  

Renal ischemia in humans and in experimental animals is associated with a complex and possibly interrelated series of events. In this study, we have investigated the glomerular nitric oxide (NO) production after renal ischemia. Unilateral or bilateral renal ischemia was induced in Wistar rats by clamping one or both renal arteries. NO production was assessed by measuring glomerular production of nitrite, a stable end product of NO catabolism, and NO-dependent glomerular cGMP production and by assessing the glomerular NADPH diaphorase (ND) activity, an enzymatic activity that colocalizes with NO-synthesis activity. Furthermore, we determined the isoform of NO synthase (NOS) implicated in NO synthesis by Western blot and immunohistochemistry. Glomeruli from rats with bilateral ischemia showed elevated glomerular nitrite and cGMP production. Besides, glomeruli from this group of rats showed an increased ND activity, whereas glomeruli from the ischemic and nonischemic rats with unilateral ischemia did not show this increase in nitrite, cGMP, and ND activity. In addition, glomeruli from ischemic kidneys showed an increased expression of endothelial NOS without changes in the inducible isoform. Addition ofl-NAME in the drinking water induced a higher increase in the severity of the functional and structural damage in rats with bilateral ischemia than in rats with unilateral ischemia and in sham-operated animals. We can conclude that after renal ischemia, there is an increased glomerular NO synthesis subsequent to an activation of endothelial NOS that plays a protective role in the renal damage induced by ischemia and reperfusion.


2011 ◽  
Vol 26 (S2) ◽  
pp. 1979-1979
Author(s):  
M. Zink ◽  
N. Segnitz ◽  
T. Ferbert ◽  
A. Schmitt ◽  
P. Gass ◽  
...  

IntroductionThe glutamatergic theory of schizophrenia proposes a dysfunction of ionotropic N-Methyl-D-aspartate (NMDA)-receptors (NR). Several therapeutic strategies address NR function and effects of antipsychotic agents on NR expression have been described.ObjectivesThe partial dopaminergic and serotonergic agonist aripiprazole (APZ) was able to counteract behavioural effects of NR antagonists, but effects of APZ on NR expression have not been investigated.AimsTo evaluate effects of APZ on NR mRNA and protein expressionMethodsWe treated Sprague-Dawley rats for 4 weeks or 4 months with APZ in daily oral doses of 10 and 40 mg per kg body weight. Expression of the NR subunits NR1, NR2A, NR2B, NR2C and NR2D was assessed by semiquantitative radioactive in situ-hybridization, and in parallel receptor binding using 3H-MK-801 receptor autoradiography.ResultsIncreased expression levels of NR1 (4 weeks), NR2A (4 weeks), NR2C (4 weeks and 4 months) and NR2D (4 months) were observed in several hippocampal and cortical brain regions. The parallel reduced expression of NR2B mRNAs (4 months) resulted in a relative increase of the NR2A/NR2B ratio. Marked differences between specific brain regions, the doses and time points of assessment became obvious. On the receptor level, increased MK-801-binding was found after 4 weeks in the 40 mg-group and after 4 months in the 10 mg-group.ConclusionsThe effects of APZ converge in enhanced NMDA-receptor expression and a shift of subunit-composition towards adult-type receptors. Our results confirm regulatory connections between dopaminergic, serotonergic and glutamatergic neurotransmission with relevance for cognitive and negative symptoms of schizophrenia.


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