title: Exaggerated natriuretic response to atrial natriuretic factor in rats developing spontaneous hypertension.
abstract: The present study was designed to evaluate the renal response to atrial natriuretic factor (ANF) in young rats developing spontaneous hypertension (SHR) and compare this response to age-matched, normotensive controls (WKY) and adult animals. At 6 weeks of age, intravenous infusion of ANF (0.25 micrograms/kg min) in anesthetized, euvolemic rats produced a significantly larger natriuresis and diuresis in SHR compared with WKY rats; this strain difference was not observed in rats 11 weeks of age. SHR showed no age-related change in the natriuretic response to ANF, whereas adult WKY rats exhibited a greater response than young WKY rats. To determine the effect of renal perfusion pressure on the magnitude of the renal response to ANF, additional groups of 6- and 11-week-old SHR were studied while renal perfusion pressure was lowered acutely by aortic constriction (SHR-AC) to values similar to age-matched WKY rats. In young rats, the diuretic and natriuretic response to ANF was greatest in SHR, intermediate in SHR-AC, and lowest in WKY rats. In adult animals, the natriuretic and diuretic response was similar in SHR and WKY rats and tended to be less in SHR-AC. These results in both 6- and 11-week-old SHR are consistent with previous reports that the magnitude of the response to ANF is directly related to acute changes in renal perfusion pressure.(ABSTRACT TRUNCATED AT 250 WORDS)
authors: Department of Physiology, University of North Carolina, Chapel Hill 27599-7545.
authors: D M
authors: DM
authors: Pollock
authors: W J
authors: WJ
authors: Arendshorst
mesh_terms: D000818:Animals; D009320:Atrial Natriuretic Factor / Q000493:pharmacokinetics / Q000494:pharmacology*; D006439:Hemodynamics / Q000187:drug effects; D006973:Hypertension / Q000503:physiopathology*; D007668:Kidney / Q000187:drug effects*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D012964:Sodium / Q000652:urine*; D013045:Species Specificity
chemical_list: D009320:Atrial Natriuretic Factor; D012964:Sodium