Baroreflex sensitivity and oxidative stress in adriamycin-induced heart failure

Citation
E. Rabelo et al., Baroreflex sensitivity and oxidative stress in adriamycin-induced heart failure, HYPERTENSIO, 38(3), 2001, pp. 576-580
Citations number
25
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Journal title
HYPERTENSION
ISSN journal
0194-911X → ACNP
Volume
38
Issue
3
Year of publication
2001
Part
2
Supplement
S
Pages
576 - 580
Database
ISI
SICI code
0194-911X(200109)38:3<576:BSAOSI>2.0.ZU;2-4
Abstract
Adriamycin cardiotoxicity is associated with oxidative stress in the presen ce of globally depressed cardiac function. It is unknown if there is a simi lar profile with early diastolic changes and how it relates to baroreflex c ontrol of circulation. In this study, we evaluated baroreflex control of ci rculation in adriamycin-treated Wistar rats compared with controls, using i nvasive blood pressure recording processed by a data acquisition system (CO DAS, 1 KHz). Baroreflex sensitivity was evaluated by modulating blood press ure with phenylephrine and sodium nitroprusside. Oxidative stress was quant ified by chemiluminescence and by glutathione peroxidase enzyme activity. D iastolic dysfunction was characterized by increased left ventricle end-dias tolic pressure in adriarnycin-treated rats compared with controls with pres erved ascending aortic flow. Baroreflex sensitivity in response to blood pr essure elevation and reduction were similar in adriamycin (-2 +/-0.27 and - 3.19 +/-0.56 bpm/mm Hg) and control rats (-1.35 +/-0.15 and -2.52 +/-0.39 b pm/mm Hg). Chemiluminescence was higher (20450 +/- 1286 versus 16517 +/- 10 20 counts per second/mg protein) and glutathione peroxidase activity was lo wer (45.6 +/-4.3 versus 76.4 +/-6.9 mu mol (.) min(-1) (.) mg(-1) protein) in adriamycin rats compared with controls. Inverse correlations were observ ed between glutathione peroxidase activity and left ventricle end-diastolic pressure (r=-0.72, P=0.02), between baroreflex sensitivity to phenylephrin e and left ventricle end-diastolic pressure (r=-0.77, P=0.004), and between chemiluminescence and baroreflex sensitivity to sodium nitroprusside (r=-0 .75, P=0.02), whereas a positive correlation was observed between barorefle x sensitivity to sodium nitroprusside and glutathione peroxidase activity ( r=0.7, P=0.04). Thus, adriamycin led to increased left ventricle end-diasto lic pressure without changes in baroreflex sensitivity, and associated incr eased oxidative stress appeared to be related to reduction of reflex contro l of circulation.