Effect of combined nitrate-fluoride intoxication on the function of NO-synthases and arginases in the gastric mucosa, blood and heart of rats

Abstract

The focus of this article is on the functioning of NO-synthases and arginases in the gastric mucosa, blood and heart of white rats under excessive intake of sodium fluoride and sodium nitrate during 30 days. Excessive intake of sodium nitrate was modeled by infusion of aqueous solution into stomach through special catheter at a dose of 500 mg / kg. Excessive intake of sodium fluoride was modeled by infusion of aqueous solution into stomach through special catheter at a dose of 10 mg / kg. The activity of these enzymes was measured by spectrophotometric methods. Analysis of the influence produced by combined nitrate-fluoride intoxication on total NOS activity in the gastric mucosa, heart and blood showed the presence of antagonistic effect of nitrates and fluorides. Nitrates act as NOS inhibitors, whereas the fluorides are inducers of NOS. Under their combined action in the organism, fluoride-induced elevation prevails over nitrate-induced inhibition, but only in tissue homogenates. Such effect is absent in blood. The inductive effect of combined nitrate-fluoride intoxication on functioning of arginases is mediated by nitrate release of L-arginin from NOS. Combined intoxication showed prevalence of inducing influence of nitrates over inhibiting effect of fluorides