The effect of an NO donor, pentaerythrityl tetranitrate, on biochemical, functional, and morphological attributes of cardiovascular system of spontaneously hypertensive rats.
The status of nitric oxide (NO) in spontaneously hypertensive rats (SHR) is unclear and its bioavailability may be affected by imbalance with reactive oxygen species. We studied cardiovascular effects of an NO donor, pentaerythrityl tetranitrate (PETN) in SHR. We used Wistar rats, SHR and SHR treated with PETN (200 mg/kg/day). After six weeks, myocardium and aorta from each group were taken for biochemical and iliac artery for functional and morphological study. Long-term administration of PETN to SHR increased cGMP level in platelets and did not affect blood pressure. In myocardium, the therapy resulted in a decrease in cardiac hypertrophy and MDA level, and the increased antioxidant enzyme activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx). In aorta, PETN decreased the NO-synthase activity and had no affect on the enzyme activities of SOD and GPx or on MDA level. In the iliac artery, the endothelium-dependent relaxation to acetylcholine was slightly improved and the maximum vasoconstriction to noradrenaline was decreased. Wall thickness, cross-sectional area, inner diameter, and wall thickness/ inner diameter measured after perfusion fixation (120 mmHg) were not affected. The small effect of PETN on cardiovascular system suggests that NO deficiency is probably not the main cause of pathological alterations in SHR.
Dovinová
Ima
I
Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Sienkiewiczova 1, 813 71 Bratislava, Slovakia. ima.dovinova@savba.sk
Cacányiová
Sona
S
Fáberová
Viera
V
Kristek
Frantisek
F
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000187:drug effects* / Q000378:metabolism; D001794:Blood Pressure / Q000187:drug effects; D006152:Cyclic GMP / Q000097:blood; D005979:Glutathione Peroxidase / Q000378:metabolism; D006321:Heart / Q000187:drug effects*; D006973:Hypertension / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D007083:Iliac Artery / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D008297:Male; D009206:Myocardium / Q000378:metabolism; D020030:Nitric Oxide Donors / Q000627:therapeutic use*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D009638:Norepinephrine / Q000494:pharmacology; D010417:Pentaerythritol Tetranitrate / Q000627:therapeutic use*; D051381:Rats; D011918:Rats, Inbred SHR; D017208:Rats, Wistar; D013482:Superoxide Dismutase / Q000378:metabolism; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology
D020030:Nitric Oxide Donors; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D010417:Pentaerythritol Tetranitrate; D005979:Glutathione Peroxidase; D019001:Nitric Oxide Synthase; D013482:Superoxide Dismutase; D006152:Cyclic GMP; D000109:Acetylcholine; D009638:Norepinephrine