Background: Dietary nitrates are known to produce nitric oxide in the stomach, which may influence gastric function.
Aim: To investigate whether nitrate ingestion modifies gastric sensitivity to distension through a mechanism involving nitric oxide production.
Methods: Nociception, associated with gastric distension ranging from 10 to 40 mmHg, was assessed in anaesthetized rats by the amplitude of cardiovascular depressor responses. Gastric volume corresponding to each distension was recorded. The following intragastric administrations (1 mL) were performed before distension: water (control), KNO3, NaNO3, KCl, NaCl (all at 0.1 mmol/kg), standard food (0.5 g), sodium nitroprusside, a nitric oxide donor (5 mg/kg), and haemoglobin, a nitric oxide scavenger (150 mg/kg) given either with water or KNO3.
Results: In controls, the fall in blood pressure increased from 7.8 +/- 2.0 to 31.6 +/- 2. 7 mmHg at distending pressures from 10 to 40 mmHg, respectively. KNO3 significantly reduced the amplitude of blood pressure response for the highest distending pressures (35 and 40 mmHg), while KCl induced a reduction in blood pressure response at all gastric pressures. NaNO3 and NaCl did not induce significant changes in distension-induced depressor responses. Administration of 0.5 g of standard food or sodium nitroprusside reproduced the effect of KNO3, which was reversed by haemoglobin. None of the compounds modified the gastric pressure-volume relationship, except KNO3, which increased gastric volume for the lowest distending pressures, and haemoglobin, which reduced the volume for the highest pressure.
Conclusions: Ingestion of potassium nitrate reduces the sensitivity to gastric distension, through a mechanism involving nitric oxide.
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http://dx.doi.org/10.1046/j.1365-2036.1999.00611.x | DOI Listing |
Plant Physiol Biochem
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Laboratory of Microbial Genetics, Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, 221005, India. Electronic address:
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Macrophage metabolism is closely linked to their phenotype and function, which is why there is growing interest in studying the metabolic reprogramming of macrophages. Bioactive glass (BG) S53P4 is a bioactive material used especially in bone applications. Additionally, BG S53P4 has been shown to affect macrophages, but the mechanisms through which the possible immunomodulatory effects are conveyed remain unclear.
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Facultad de Química, Universidad Autónoma de Yucatán (UADY), Calle 43 S/N entre calle 96 y calle 40 Colonia Inalámbrica, Mérida, Yucatán, C.P. 97069, Mexico.
Chagas disease is a chronic infection caused by the protozoan parasite, Trypanosoma cruzi, with limited benefits of the currently available anti-parasitic chemotherapeutic approaches to halt the progression of heart disease. Recombinant TSA-1-C4 and Tc24-C4 proteins have been developed as promising antigen candidates for therapeutic vaccines, leading to propose them in combination as a bivalent recombinant protein strategy. In this study, we evaluated the immunomodulatory effect of the combined TSA-1-C4 and Tc24-C4 recombinant proteins by in vitro assays using murine macrophages.
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