Different effects of losartan and moxonidine on endothelial function during sympathetic activation in essential hypertension.
The aim of this study was to investigate: 1) the effects of treadmill exercise on plasma catecholamines and endothelin-1 (ET-1, a potent vasoconstrictor) levels in hypertensive patients; and 2) the impact of 1-month therapy with losartan as compared with moxonidine on catecholamine and ET-1 changes during exercise. Twenty-eight patients with essential hypertension were randomized in two groups: group A received losartan and group B received moxonidine for 1 month. Plasma catecholamines exhibited an almost 10-fold increase during exercise (p<0.00001) before treatment. Moxonidine significantly decreased catecholamine levels (p<0.05), while losartan reduction was nonsignificant (p<0.36). Plasma ET-1 increased significantly during exercise before treatment (p<0.00005). Moxonidine therapy did not affect ET-1 levels (p<0.88), while losartan resulted in a significant decrease of ET-1 levels both at baseline and during exercise (p<0.007). These findings suggest a mechanism for the reduced cardiovascular mortality noted with an angiotensin receptor blocker as compared with a sympatholytic agent.
Doumas
Michael N
MN
Second Propedeutic Department of Internal Medicine, Hippokration Hospital, Aristotelian University of Thessaloniki, Thessaloniki, Greece. michalisdoumas@yahoo.co.uk
Douma
Stella N
SN
Petidis
Kostas M
KM
Vogiatzis
Kostas V
KV
Bassagiannis
Ilias C
IC
Zamboulis
Chris X
CX
D047228:Angiotensin II Type 1 Receptor Blockers / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D002395:Catecholamines / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D019332:Endothelin-1 / Q000097:blood; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology*; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000188:drug therapy* / Q000503:physiopathology; D007093:Imidazoles / Q000627:therapeutic use*; D019808:Losartan / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000503:physiopathology*; D013565:Sympatholytics / Q000627:therapeutic use*; D016896:Treatment Outcome
D047228:Angiotensin II Type 1 Receptor Blockers; D015415:Biomarkers; D002395:Catecholamines; D019332:Endothelin-1; D007093:Imidazoles; D013565:Sympatholytics; C043482:moxonidine; D019808:Losartan