Paradoxical actions of the NO donor SIN-I on single laryngeal motoneurons in the nucleus ambiguus

We have previously reported that both l-glutamate (l-Glu) and nitric oxide (NO) modulate gastric motility in the nucleus ambiguus (NA). The aim of this study is to explore the potential correlation between the l-Glu and NO. A latex balloon connected to a pressure transducer was inserted into the pylorus through the fundus of anesthetized male Wistar rats to continuously record changes in gastric smooth muscle contractile curves. Pretreatment with the NO-synthase inhibitor N-nitro-l-arginine methylester (l-NAME) did not completely abolish the inhibitory effect of l-Glu on gastric motility, but intravenous injection of the ganglionic blocker hexamethonium bromide (Hb) did. By using a specific N-methyl-d-aspartic acid (NMDA) receptor antagonist, we blocked the inhibitory effect of the NO-donor sodium nitroprusside (SNP) on gastric motility. These results suggest that microinjections of l-Glu into the NA inhibits gastric motility by activating the cholinergic preganglionic neurons, partially through the NMDA receptor – NO pathway.

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Cytoarchitectonic organization of laryngeal motoneurons within the nucleus ambiguus of the cat

Experimental Neurology ◽

10.1016/0014-4886(83)90085-7 ◽

1983 ◽

Vol 82 (3) ◽

pp. 623-634 ◽

Cited By ~ 25

Author(s):

R. Pásaro ◽

B. Lobera ◽

S. González-Barón ◽

J.M. Delgado-García

Keyword(s):

Nucleus Ambiguus ◽

Laryngeal Motoneurons

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Monosynaptic inputs from the nucleus tractus solitarii to the laryngeal motoneurons in the nucleus ambiguus of the rat

Anatomy and Embryology ◽

10.1007/s004290000120 ◽

2000 ◽

Vol 202 (5) ◽

pp. 411-420 ◽

Cited By ~ 15

Author(s):

T. Hayakawa ◽

Akinori Takanaga ◽

Seishi Maeda ◽

Hisao Ito ◽

Makoto Seki

Keyword(s):

Nucleus Tractus Solitarii ◽

Nucleus Ambiguus ◽

Laryngeal Motoneurons

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Localization of rabbit laryngeal motoneurons in the nucleus ambiguus

Experimental Neurology ◽

10.1016/0014-4886(87)90216-0 ◽

1987 ◽

Vol 96 (3) ◽

pp. 528-539 ◽

Cited By ~ 15

Author(s):

Johji Okubo ◽

Seiichiro Kitamura ◽

Kimio Ogata ◽

Akira Sakai

Keyword(s):

Nucleus Ambiguus ◽

Laryngeal Motoneurons

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Potential of Motor Neurons in the Nucleus Ambiguus ∼ Utilizing Nestin-EGFP Transgenic Rats

Nihon Kikan Shokudoka Gakkai Kaiho ◽

10.2468/jbes.58.193 ◽

2007 ◽

Vol 58 (2) ◽

pp. 193-193

Author(s):

T. Takaoka ◽

A. Shiotani ◽

K. Saito ◽

M. Tomifuji ◽

Y. Mori ◽

...

Keyword(s):

Motor Neurons ◽

Nucleus Ambiguus ◽

Transgenic Rats

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Nω-Hydroxy-L-arginine and Its Homologues. Chemical and Biological Properties. A Review

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20040499 ◽

2004 ◽

Vol 69 (3) ◽

pp. 499-510 ◽

Cited By ~ 1

Author(s):

Petra Beranová ◽

Karel Chalupský ◽

Gustav Entlicher

Keyword(s):

Inhibitory Activity ◽

Biological Activities ◽

Biological Effects ◽

Biological Properties ◽

No Synthase ◽

Point Of View ◽

No Donor ◽

Good Substrate ◽

No Formation ◽

Vasorelaxant Activity

Nω-Hydroxy-L-arginine (NOHA) is a stable intermediate in NO formation from L-arginine catalyzed by NO synthase (NOS). Apparently, NOHA can be released and serve as a stable reserve NO donor (as a substrate of NOS) or transported and exert its own biological effects. It shows endothelium-dependent as well as endothelium-independent vasorelaxant activity. The latter case indicates that NOHA can be metabolized by pathways independent of NOS. These possibilities are discussed in detail. Of the available NOHA homologues homo-NOHA is a good substrate of NOS while nor-NOHA seems to be a very poor substrate of this enzyme. On the contrary, nor-NOHA exerts arginase inhibitory activity 20 times higher than NOHA whereas homo-NOHA is inactive. Detailed investigation of biological activities of NOHA and its homologues seems to be promising from the pharmacological point of view. A review with 43 references.

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Effects ofS-nitroso-N-acetylcysteine on contractile function of reperfused skeletal muscle

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1998.274.3.r822 ◽

1998 ◽

Vol 274 (3) ◽

pp. R822-R829 ◽

Cited By ~ 8

Author(s):

Long-En Chen ◽

Anthony V. Seaber ◽

Rima M. Nasser ◽

Jonathan S. Stamler ◽

James R. Urbaniak

Keyword(s):

Skeletal Muscle ◽

Reperfusion Injury ◽

Contractile Function ◽

Ischemia Reperfusion ◽

Protective Role ◽

Control Group ◽

Group Vi ◽

No Donor ◽

Early Reperfusion ◽

Reconstructive Operations

The ultimate goal of replantation and microsurgical reconstructive operations is to regain or improve impaired function of the tissue. However, the data related to the influence of NO on tissue function are limited. This study evaluated the effects of the NO donor S-nitroso- N-acetylcysteine (SNAC) on contractile function of skeletal muscle during reperfusion. Forty-nine rats were divided into six groups. The extensor digitorum longus (EDL) muscles in groups I and II were not subjected to ischemia-reperfusion but were treated with a low (100 nmol/min) or high (1 μmol/min) dose of SNAC. In groups III- V, the EDL underwent 3 h of ischemia and 3 h of reperfusion and was also treated with low (100 nmol/min) or high doses (1 or 5 μmol/min) of SNAC. Group VI was a phosphate-buffered saline (PBS)-treated control group. Twenty additional animals were used to document systemic effects of SNAC and PBS only. SNAC or PBS was infused for 6.5 h, beginning 30 min before ischemia and continuing throughout the duration of reperfusion. Contractile testing compared the maximal twitch force, isometric tetanic contractile forces, fatigue, and fatigue half time of the experimental EDL and the contralateral nontreated EDL. The findings indicate that 1) SNAC does not influence contractile function of EDL muscle not subjected to ischemia-reperfusion, 2) SNAC significantly protects the contractile function of ischemic skeletal muscle against reperfusion injury in the early reperfusion period, and 3) the protective role of SNAC is critically dosage dependent; protection is lost at higher doses. The conclusion from this study is that supplementation with exogenous NO exerts a protective effect on the tissue against reperfusion injury.

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Florigen governs shoot regeneration

Scientific Reports ◽

10.1038/s41598-021-93180-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yaarit Kutsher ◽

Michal Fisler ◽

Adi Faigenboim ◽

Moshe Reuveni

Keyword(s):

Nitric Oxide ◽

Shoot Regeneration ◽

Ectopic Expression ◽

Flowering Plants ◽

Regeneration Capacity ◽

No Donor ◽

Tobacco Leaves ◽

Age Related ◽

Delayed Flowering

AbstractIt is widely known that during the reproductive stage (flowering), plants do not root well. Most protocols of shoot regeneration in plants utilize juvenile tissue. Adding these two realities together encouraged us to study the role of florigen in shoot regeneration. Mature tobacco tissue that expresses the endogenous tobacco florigen mRNA regenerates poorly, while juvenile tissue that does not express the florigen regenerates shoots well. Inhibition of Nitric Oxide (NO) synthesis reduced shoot regeneration as well as promoted flowering and increased tobacco florigen level. In contrast, the addition of NO (by way of NO donor) to the tissue increased regeneration, delayed flowering, reduced tobacco florigen mRNA. Ectopic expression of florigen genes in tobacco or tomato decreased regeneration capacity significantly. Overexpression pear PcFT2 gene increased regeneration capacity. During regeneration, florigen mRNA was not changed. We conclude that florigen presence in mature tobacco leaves reduces roots and shoots regeneration and is the possible reason for the age-related decrease in regeneration capacity.

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Extra-platelet low-molecular-mass thiols mediate the inhibitory action of S-nitrosoalbumin on human platelet aggregation via S-transnitrosylation of the platelet surface

Amino Acids ◽

10.1007/s00726-021-02950-8 ◽

2021 ◽

Author(s):

Dimitrios Tsikas

Keyword(s):

Platelet Aggregation ◽

Molecular Mass ◽

Underlying Mechanism ◽

Selective Extraction ◽

Post Translational Modification ◽

No Donor ◽

Platelet Surface ◽

Sh Groups ◽

Human Platelet Aggregation ◽

Inhibitory Potential

AbstractNitrosylation of sulfhydryl (SH) groups of cysteine (Cys) moieties is an important post-translational modification (PTM), often on a par with phosphorylation. S-Nitrosoalbumin (ALB-Cys34SNO; SNALB) in plasma and S-nitrosohemoglobin (Hb-Cysβ93SNO; HbSNO) in red blood cells are considered the most abundant high-molecular-mass pools of nitric oxide (NO) bioactivity in the human circulation. SNALB per se is not an NO donor. Yet, it acts as a vasodilator and an inhibitor of platelet aggregation. SNALB can be formed by nitrosation of the sole reduced Cys group of albumin (Cys34) by nitrosating species such as nitrous acid (HONO) and nitrous anhydride (N2O3), two unstable intermediates of NO autoxidation. SNALB can also be formed by the transfer (S-transnitrosylation) of the nitrosyl group (NO+) of a low-molecular-mass (LMM) S-nitrosothiol (RSNO) to ALB-Cys34SH. In the present study, the effects of LMM thiols on the inhibitory potential of ALB-Cys34SNO on human washed platelets were investigated. ALB-Cys34SNO was prepared by reacting n-butylnitrite with albumin after selective extraction from plasma of a healthy donor on HiTrapBlue Sepharose cartridges. ALB-Cys34SNO was used in platelet aggregation measurements after extended purification on HiTrapBlue Sepharose and enrichment by ultrafiltration (cutoff, 20 kDa). All tested LMM cysteinyl thiols (R-CysSH) including l-cysteine and L-homocysteine (at 10 µM) were found to mediate the collagen-induced (1 µg/mL) aggregation of human washed platelets by SNALB (range, 0–10 µM) by cGMP-dependent and cGMP-independent mechanisms. The LMM thiols themselves did not affect platelet aggregation. It is assumed that the underlying mechanism involves S-transnitrosylation of SH groups of the platelet surface by LMM RSNO formed through the reaction of SNALB with the thiols: ALB-Cys34SNO + R-CysSH ↔ ALB-Cys34SH + R-CysSNO. Such S-transnitrosylation reactions may be accompanied by release of NO finally resulting in cGMP-dependent and cGMP-independent mechanisms.

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