title: Differing hemodynamic responses to atrial natriuretic factor in two models of hypertension.
abstract: Hemodynamic responses to synthetic atrial natriuretic factor (ANF), were studied in renin-dependent two-kidney, one-clip (2K,1C) and deoxycorticosterone (DOC) salt-treated hypertensive rats as well as normotensive controls. ANF infusion (800 pmol/kg prime, 120 pmol X kg-1 X min-1 for 60 min) decreased blood pressure (BP) more in conscious 2K,1C (-24 +/- 4%) than in DOC salt-treated (-12 +/- 4%, P less than 0.05) or control rats. Hemodynamic parameters were also evaluated during graded infusion of three doses, each for 30 min. At 24 and 120 pmol X kg-1 X min-1, ANF lowered BP in 2K,1C rats, both conscious (from 156 +/- 6 to 144 +/- 7, P less than 0.05 and 135 +/- 5 mmHg, P less than 0.05) and anesthetized (from 148 +/- 7 to 138 +/- 7, P less than 0.05 and 128 +/- 7, P less than 0.05). In anesthetized 2K,1C, BP changes were associated with reduction in total peripheral resistance (TPR) that became significant at 120 pmol X kg-1 X min-1 (-10 +/- 2%), whereas cardiac output (CO) and stroke volume (SV) were unchanged. In DOC-salt-treated rats these doses did not lower BP despite progressive falls in CO (-7 +/- 3% and -24 +/- 5%, P less than 0.05) and SV (-8 +/- 2% and -23 +/- 5%, P less than 0.05), which were balanced by a simultaneous rise in TPR (+12 +/- 4% and +26 +/- 10%, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D003250:Constriction; D003900:Desoxycorticosterone; D004305:Dose-Response Relationship, Drug; D006439:Hemodynamics / Q000187:drug effects*; D006973:Hypertension / Q000139:chemically induced / Q000503:physiopathology*; D006978:Hypertension, Renovascular / Q000209:etiology / Q000503:physiopathology; D007668:Kidney; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012965:Sodium Chloride
chemical_list: D003900:Desoxycorticosterone; D012965:Sodium Chloride; D009320:Atrial Natriuretic Factor