Prolonged converting enzyme inhibition in non-modulating hypertension.
Patients with normal- or high-renin non-modulating essential hypertension fail to shift their adrenal sensitivity on a low sodium diet in response to an infusion of angiotensin II (Ang II). In a prior study, 72 hours of converting enzyme inhibition (CEI) partially corrected this subnormal aldosterone response to Ang II in patients with non-modulating hypertension. Since it was uncertain whether the failure to restore normal adrenal responsiveness reflected a continued abnormality or an insufficient duration of CEI, the present study was performed wherein subjects were studied before CEI and then 72 hours and 6 weeks after CEI. Adrenal and renovascular responses were assessed in 13 subjects with normal- or high-renin hypertension in response to an infusion of Ang II (0.3, 1.0, and 3.0 ng/kg/min) in balance on a 10 meq Na+/100 meq K+ diet. Eight of 13 had a normal plasma aldosterone increment above control levels (greater than or equal to 15 ng/dl) and were classified as modulators; the remaining subjects (five of 13) were classified as non-modulators. Enalapril was then administered for 72 hours and 6 weeks, and the assessment of the Ang II dose-response relations was repeated. In the modulators, there was no change compared with levels before CEI in the aldosterone dose-response curve or threshold sensitivity to infused Ang II at either 3 days or 6 weeks after CEI administration. In the non-modulators, CEI for 72 hours partially restored aldosterone responsiveness, but more prolonged CEI for 6 weeks completely corrected the defect, restoring aldosterone responsiveness on a sodium-restricted diet to that seen in modulators and in normotensive control subjects.(ABSTRACT TRUNCATED AT 400 WORDS)
Dluhy
R G
RG
Endocrine-Hypertension Unit, Brigham and Women's Hospital, Boston, Massachusetts 02115.
Smith
K
K
Taylor
T
T
Hollenberg
N K
NK
Williams
G H
GH
D000450:Aldosterone / Q000097:blood; D000804:Angiotensin II / Q000008:administration & dosage / Q000097:blood; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D004039:Diet, Sodium-Restricted; D004305:Dose-Response Relationship, Drug; D004656:Enalapril / Q000008:administration & dosage; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D012079:Renal Circulation / Q000187:drug effects; D012083:Renin / Q000097:blood; D012084:Renin-Angiotensin System / Q000187:drug effects; D013997:Time Factors; D010130:p-Aminohippuric Acid
D000806:Angiotensin-Converting Enzyme Inhibitors; D000804:Angiotensin II; D000450:Aldosterone; D004656:Enalapril; D012083:Renin; D010130:p-Aminohippuric Acid