Effects of antihypertensive agents, alpha receptor blockers, beta blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers and calcium channel blockers, on oxidative stress.
BACKGROUND
Free oxygen radicals and insufficiency of antioxidant enzymes have been implicated in the pathogenesis of hypertension disease (HD). Trace elements function as a co-factor in antioxidant enzymes. The antioxidant system and trace elements have been investigated in many different studies including HD, but these subjects have not been investigated as a whole in these patients.


OBJECTIVE
The aim of the present study was to investigate the antioxidative system and trace elements in hypertensive patients given different antihypertensive therapy.


METHODS
We examined malondialdehyde and superoxide dismutase activities together with copper and zinc levels in plasma of 102 patients with HD and in 51 healthy controls.


RESULTS
It was found that in patients with HD, plasma malondialdehyde was significantly higher than those of controls, while plasma superoxide dismutase activities were significantly lower in patients with HD. Plasma zinc levels were significantly higher than those of controls and plasma copper levels were significantly lower in patients with HD. Plasma lipid levels and oxidative state were analyzed in five different treatment groups given antihypertensive drug therapy before and after a 3-month treatment period.


CONCLUSIONS
In conclusion, our clinical study shows that angiotensin-converting enzyme inhibitors and angiotensin receptor blockers have notable effects on oxidative stress, and are an essential step in managing essential hypertension by the way of improvement of endothelial dysfunction. Although it has been shown that calcium channel blockers, beta blockers and alpha receptor blockers have antioxidant effects in in vitro conditions, we did not demonstrate these effects in our clinical study.
Baykal
Yavuz
Y
Department of Internal Medicine, Gülhane School of Medicine, Etlik-Ankara, Turkey. mahmutiyilmaz@yahoo.com
Yilmaz
M Ilker
MI
Celik
Turgay
T
Gok
Faysal
F
Rehber
Hamiyet
H
Akay
Cemal
C
Kocar
I Hakki
IH
D000317:Adrenergic alpha-Antagonists / Q000008:administration & dosage; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage; D000328:Adult; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D002121:Calcium Channel Blockers / Q000008:administration & dosage; D003300:Copper / Q000097:blood; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000188:drug therapy*; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D013482:Superoxide Dismutase / Q000097:blood; D015032:Zinc / Q000097:blood
D000317:Adrenergic alpha-Antagonists; D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D002121:Calcium Channel Blockers; D008315:Malondialdehyde; D003300:Copper; D013482:Superoxide Dismutase; D015032:Zinc