Dovinová Ima, Cacányiová Sona, Fáberová Viera, Kristek Frantisek
Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Sienkiewiczova 1, 813 71 Bratislava, Slovakia.
Gen Physiol Biophys. 2009 Mar;28(1):86-93.
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.
一氧化氮（NO）在自发性高血压大鼠（SHR）中的状态尚不清楚，其生物利用度可能受到与活性氧失衡的影响。我们研究了NO供体季戊四醇四硝酸酯（PETN）对SHR心血管系统的影响。我们使用了Wistar大鼠、SHR以及用PETN（200mg/kg/天）治疗的SHR。六周后，采集每组大鼠的心肌和主动脉用于生化研究，采集髂动脉用于功能和形态学研究。对SHR长期给予PETN可提高血小板中的环磷酸鸟苷（cGMP）水平，且不影响血压。在心肌中，该治疗导致心脏肥大和丙二醛（MDA）水平降低，超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GPx）的抗氧化酶活性增加。在主动脉中，PETN降低了一氧化氮合酶（NO-synthase）的活性，对SOD和GPx的酶活性或MDA水平没有影响。在髂动脉中，对乙酰胆碱的内皮依赖性舒张略有改善，对去甲肾上腺素的最大血管收缩作用降低。灌注固定（120mmHg）后测量的壁厚、横截面积、内径和壁厚/内径不受影响。PETN对心血管系统的影响较小，这表明NO缺乏可能不是SHR病理改变的主要原因。
