Open AccessThe Angiotensin II-Receptor Antagonist Losartan Does Not Prevent Hemodynamic or Vascular Tolerance to Nitroglycerin
Author(s) -
Stephen D. Milone,
Eduardo Ribeiro de Azevêdo,
Christine Förster,
John D. Parker
Publication year - 1999
Publication title -
journal of cardiovascular pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.762
H-Index - 100
eISSN - 1533-4023
pISSN - 0160-2446
DOI - 10.1097/00005344-199911000-00004
Subject(s) - losartan , medicine , angiotensin ii , transdermal , placebo , angiotensin ii receptor antagonist , pharmacology , blood pressure , antagonist , anesthesia , receptor , alternative medicine , pathology
Tolerance may involve increased production of angiotensin II. We tested the hypothesis that losartan would prevent the development of tolerance to continuous transdermal nitroglycerin (GTN). Twenty volunteers received losartan, 75 mg/day, or placebo in a randomized, double-blind, parallel fashion. After 1 week, continuous transdermal GTN, 0.6 mg/h, was given, in addition to losartan or placebo, to all volunteers for 1 week. Standing systolic blood pressure (SBP) and heart rate were measured, and forearm venous volume responses to sublingual GTN were evaluated. Measurements were made at baseline, after 1 week of losartan versus placebo, 3 h after initial therapy with transdermal GTN, and after 1 week of continuous transdermal GTN given in combination with losartan versus placebo. After sustained GTN therapy, SBP was unchanged from baseline in both groups, indicating that losartan did not prevent the development of tolerance. Tolerance also developed to the forearm venous volume responses and was not prevented by losartan. Therapy with an angiotensin II-receptor antagonist does not prevent the development of tolerance to continuous transdermal GTN.