Effect of Hypotensive Drugs on Dynamics of Nitroxide-Producing Renal Function in Rats with Nephrogenic Hypertension

Resumo

An original model of nephrogenic hypertension in rats was used for histochemical mapping of NADPH diaphorase (NO synthase) in various renal segments to examine the effect of hypotensive drugs furosemide, bendazol, and clonidine on the time course of nitroxide production in the kidneys. In various nephron segments, these drugs modulated NO synthesis in different ways. Clonidine induced a stable up-regulation of NO synthesis, which can maintain active vasodilation and gradually diminish the rennin production. Bendazol also enhanced NO synthase activity in renal glomeruli and collecting tubules, but this effect was less pronounced and short lasting. During the first week after injection of bendazol, insignificant elevation of NO synthase activity was observed in the proximal nephron segments. Furosemide exerted the least effect on NO production in kidneys.