title: [Comparative effects of losartan and amlodipine on activities of sympathetic nerve, renin-angiotensin-aldosterone system and brain natriuretic peptide in the elderly hypertensive patients].
abstract: This study investigated the comparative effects of losartan and amlodipine on the activation of the sympathetic nervous system, renin-angiotensin-aldosterone system (R-A-A system) and brain natriuretic peptide (BNP) in patients with essential hypertension. Twenty-four elderly patients who had received more than 12 months of antihypertensive treatment with amlodipine participated in this study. The treatment regimen of 5 mg/day amlodipine was changed to 50 mg/day losartan. Plasma catecholamines (norepinephrine, epinephrine and dopamine), active renin, aldosterone and BNP concentration were measured before and after an average of 5 months of losartan treatment. After losartan treatment, blood pressures were not changed, suggesting the comparable effect of 50 mg losartan and 5 mg amlodipine on elevated blood pressure. Losartan significantly reduced norepinephrine (799 +/- 277 pg/mL vs. 692 +/- 268 pg/mL, p < 0.05) and aldosterone concentration (81.2 +/- 35.3 pg/mL vs. 55.2 +/- 17.7 pg/mL, p < 0.01), whereas there were not any changes in BNP concentrations. These findings suggested that losartan might be superior to amlodipine in prevention of chronic or intermittent sympathetic hyperactivity and enhanced R-A-A system.
authors.affiliation: First Department of Internal Medicine, Shiga University of Medical Science.
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Tsutamoto
authors.forename: Keiko
authors.initials: K
authors.lastname: Maeda
authors.forename: Naoko
authors.initials: N
authors.lastname: Mabuchi
authors.forename: Takashi
authors.initials: T
authors.lastname: Tsutsui
authors.forename: Masato
authors.initials: M
authors.lastname: Ohnishi
authors.forename: Masahiko
authors.initials: M
authors.lastname: Kinoshita
mesh_terms: D000368:Aged; D017311:Amlodipine / Q000494:pharmacology*; D000959:Antihypertensive Agents / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology*; D019808:Losartan / Q000494:pharmacology*; D020097:Natriuretic Peptide, Brain / Q000378:metabolism*; D012084:Renin-Angiotensin System / Q000187:drug effects*; D013564:Sympathetic Nervous System / Q000187:drug effects*
chemical_list: D000959:Antihypertensive Agents; D002121:Calcium Channel Blockers; D020097:Natriuretic Peptide, Brain; D017311:Amlodipine; D019808:Losartan