Effects of nitric oxide donor and nitric oxide synthase inhibitor on ruminal contractions in conscious sheep

Onaga, Takenori; Okada, Hiroyuki; Hagiwara, Satoshi; Nagashima, Chihiro; Inoue, Hiroki; Korczyński, W.; Kato, Shinichi

doi:10.1053/rvsc.2001.0507

Cited by 6 publications

(9 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4, and 5), and the saline infusion did not significantly change either parameter. Consistent with our previous observations (Onaga et al 2001), intravenous L-NAME infusion did not alter the frequency of ruminal contractions. Though L-NAME tended to inhibit the amplitude of ruminal contractions at the highest dose, the changes were not significant compared to the value before infusion and that at the same time point in saline infusion.…”

Section: Effect Of Snap On Ovine Gastric Motilitysupporting

confidence: 93%

“…The present study demonstrated that intravenous infusion of the NO donor, SNAP, inhibited omasal EMG activity in healthy sheep at doses that inhibited regular ruminal contraction (Onaga et al 2001), whereas it did not alter EMG activity of the ovine abomasal antrum. SNAP application to smooth muscle strips of the omasal greater curvature also inhibited BCh-induced contractions of both the longitudinal and circular muscles, and the inhibition was more potent in the latter than in the former.…”

Section: Discussionmentioning

confidence: 51%

“…In the second series of experiments, L-NAME was infused (i. v.) in the second 20-min period at doses of 0.3, 1.0, or 3.0 μmol/kg per min. The dose ranges for SNAP and L-NAME were determined on the basis of our previous studies (Onaga et al 2000(Onaga et al , 2001; that is, ranges at which i. v. infusion of SNAP inhibited regular ruminal contractions in sheep, and at which L-NAME infusion induced clusters of contractions similar to premature phase III activity of MMC in the duodenum.…”

Section: Methodsmentioning

confidence: 99%

“…In the rumen and reticulum, whereas the application of L-NAME has been shown to inhibit electrical field stimulation-induced relaxation of the bovine smooth muscle strips (Schneider and Eades 1998), our previous study demonstrated that intravenous infusion of L-NAME did not alter regular ruminal contractions in healthy sheep (Onaga et al 2001), indicating that endogenous NO is not involved in the regulation of regular ruminal contractions in conscious healthy sheep. This conflict between results indicates that the role of endogenous NO differs according to the experimental conditions.…”

Section: Introductionmentioning

confidence: 93%

“…The effect of SNAP on ruminal contractions was examined as the positive control (Onaga et al 2001). In the control experiments, regular primary ruminal contractions occurred (Fig.…”

Section: Effect Of Snap On Ovine Gastric Motilitymentioning

confidence: 99%

See 4 more Smart Citations

Role of nitrergic nerves in the regulation of motility of the omasum and abomasum in healthy sheep (Ovis aries)

2008

View full text Add to dashboard Cite

We examined the physiological role of nitrergic nerves in the regulation of omasal and abomasal motility in conscious healthy sheep and omasal muscle specimens. Nitric oxide (NO)-donor, S-nitroso-acethyl-dl-penicillamine (SNAP, 3-30 nmol/kg per min, i.v.) significantly inhibited omasal electromyographic (EMG) activity, whereas it did not alter EMG activity in the abomasal antrum. However, NO synthase inhibitor, Nomega-nitro-l-arginine-methyl ester (L-NAME, 0.3-3.0 micromol/kg per min, i.v.) did not alter EMG activity of the omasum and abomasum. In the in vitro experiments, SNAP application (6-200 micromol/l) significantly inhibited bethanechol (10 micromol/l)-induced contraction of longitudinal and circular muscles of the omasum. L-NAME application (0.03-3.0 mmol/l) enhanced electric field stimulation-induced contractions of the circular muscles. The results suggest that the omasal muscles are responsive to exogenous NO and that nitrergic nerves innervate the circular muscle layer of the omasum, however, nitrergic nerves are not or scarcely involved the physiological regulation of omasal and possibly abomasal motility in healthy sheep.

show abstract

Section: Effect Of Snap On Ovine Gastric Motilitysupporting

confidence: 93%

Section: Discussionmentioning

confidence: 51%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 93%

“…The effect of SNAP on ruminal contractions was examined as the positive control (Onaga et al 2001). In the control experiments, regular primary ruminal contractions occurred (Fig.…”

Section: Effect Of Snap On Ovine Gastric Motilitymentioning

confidence: 99%

See 3 more Smart Citations

Role of nitrergic nerves in the regulation of motility of the omasum and abomasum in healthy sheep (Ovis aries)

2008

View full text Add to dashboard Cite

show abstract

Dose-response effect of encapsulated nitrate replacing soybean meal on growth performance, ingestive behavior, and blood metabolites of feedlot finishing bulls

Araújo¹,

Pereira

Couto

et al. 2021

Livestock Science

View full text Add to dashboard Cite

Managing the rumen to limit the incidence and severity of nitrite poisoning in nitrate-supplemented ruminants

et al. 2016

View full text Add to dashboard Cite

Inclusion of nitrate (NO3−) in ruminant diets is a means of increasing non-protein nitrogen intake while at the same time reducing emissions of enteric methane (CH4) and, in Australia, gaining carbon credits. Rumen microorganisms contain intracellular enzymes that use hydrogen (H2) released during fermentation to reduce NO3− to nitrite (NO2−), and then reduce the resulting NO2− to ammonia or gaseous intermediates such as nitrous oxide (N2O) and nitric oxide (NO). This diversion of H2 reduces CH4 formation in the rumen. If NO2− accumulates in the rumen, it may inhibit growth of methanogens and other microorganisms and this may further reduce CH4 production, but also lower feed digestibility. If NO2− is absorbed and enters red blood cells, methaemoglobin is formed and this lowers the oxygen-carrying capacity of the blood. Nitric oxide produced from absorbed NO2− reduces blood pressure, which, together with the effects of methaemoglobin, can, at times, lead to extreme hypoxia and death. Nitric oxide, which can be formed in the gut as well as in tissues, has a variety of physiological effects, e.g. it reduces primary rumen contractions and slows passage of digesta, potentially limiting feed intake. It is important to find management strategies that minimise the accumulation of NO2−; these include slowing the rate of presentation of NO3– to rumen microbes or increasing the rate of removal of NO2−, or both. The rate of reduction of NO3− to NO2− depends on the level of NO3− in feed and its ingestion rate, which is related to the animal’s feeding behaviour. After NO3− is ingested, its peak concentration in the rumen depends on its rate of solubilisation. Once in solution, NO3− is imported by bacteria and protozoa and quickly reduced to NO2−. One management option is to encapsulate the NO3− supplement to lower its solubility. Acclimating animals to NO3− is an established management strategy that appears to limit NO2− accumulation in the rumen by increasing microbial nitrite reductase activity more than nitrate reductase activity; however, it does not guarantee complete protection from NO2− poisoning. Adding concentrates into nitrate-containing diets also helps reduce the risk of poisoning and inclusion of microbial cultures with enhanced NO2−-reducing properties is another potential management option. A further possibility is to inhibit NO2− absorption. Animals differ in their tolerance to NO3− supplementation, so there may be opportunities for breeding animals more tolerant of dietary NO3−. Our review aims to integrate current knowledge of microbial processes responsible for accumulation of NO2− in rumen fluid and to identify management options that could minimise the risks of NO2− poisoning while reducing methane emissions and maintaining or enhancing livestock production.

show abstract

Effects of nitric oxide donor and nitric oxide synthase inhibitor on ruminal contractions in conscious sheep

Cited by 6 publications

References 18 publications

Role of nitrergic nerves in the regulation of motility of the omasum and abomasum in healthy sheep (Ovis aries)

Role of nitrergic nerves in the regulation of motility of the omasum and abomasum in healthy sheep (Ovis aries)

Dose-response effect of encapsulated nitrate replacing soybean meal on growth performance, ingestive behavior, and blood metabolites of feedlot finishing bulls

Managing the rumen to limit the incidence and severity of nitrite poisoning in nitrate-supplemented ruminants

Contact Info

Product

Resources

About