Mechanism of structural remodelling of the rat aorta during long-term NG-nitro-L-arginine methyl ester treatment.
The aim of the present study was to determine whether decreased nitric oxide (NO) synthase production or rather N(G)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension was responsible for metabolic and structural remodelling of the rat aorta during four-week L-NAME treatment. Three groups of male Wistar rats were investigated: control, treated with 20 mg/kg per day L-NAME (L-NAME20), and treated with 40 mg/kg per day L-NAME (L-NAME40). Systolic blood pressure significantly increased in L-NAME20 to 146% and in L-NAME40 to 149% of the control value. NO synthase activity in the aorta significantly decreased in L-NAME20 and L-NAME40 to 86% and 65% of the control values, respectively. Proteosynthesis was significantly elevated in both L-NAME groups, while nuclear DNA concentration was significantly elevated only in the L-NAME40 group. Cyclic GMP concentration significantly decreased in L-NAME20 to 73% and in L-NAME40 to 46% of the control. Cyclic AMP concentration significantly increased in L-NAME20 and L-NAME40 to 128% and 145% of the control value, respectively. The diameter and wall thickness-to-diameter ratio were significantly elevated only in the L-NAME40 group. We conclude that remodelling of the aorta in L-NAME-treated rats was rather associated with NO deficiency than L-NAME-induced hypertension.
Bernátová
I
I
Department of Cardiovascular Physiology, Institute of Normal and Pathological Physiology, Slovak Academy of Sciences, Bratislava, Slovak Republic.
Pechánová
O
O
Kristek
F
F
D000818:Animals; D001013:Aorta, Thoracic / Q000033:anatomy & histology / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D001794:Blood Pressure / Q000187:drug effects; D002250:Carbon Radioisotopes; D000242:Cyclic AMP / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000633:toxicity*; D007930:Leucine / Q000378:metabolism; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000633:toxicity*; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D051381:Rats; D017208:Rats, Wistar
D002250:Carbon Radioisotopes; D004791:Enzyme Inhibitors; D009569:Nitric Oxide; D004247:DNA; D000242:Cyclic AMP; D019001:Nitric Oxide Synthase; D007930:Leucine; D019331:NG-Nitroarginine Methyl Ester