Copper-marginal and copper-deficient diets decrease aortic prostacyclin production and copper-dependent superoxide dismutase activity, and increase aortic lipid peroxidation in rats.
Agonist challenged aortic prostacyclin production was examined in copper-adequate, -marginal and -deficient rats fed AIN-based diets providing 6.7, 1.7 and 0.8 micrograms Cu/g, respectively. Aortic rings were incubated in Krebs-Henseleit salts, 10 mmol/L HEPES buffer, pH 7.4, 95%:5% O2:CO2, 37 degrees C, and equilibrated for 1 h. Equilibrated rings were challenged with buffer (basal), 273.0 nmol/L thrombin and angiotensin II at 84.6 pmol/L and 846.0 pmol/L. Prostacyclin production, determined at 10 minutes by RIA as 6-keto prostaglandin F1 alpha, in basal and 84.6 pmol/L angiotensin II ring incubations was significantly reduced by 28 to 48% in copper-deficient rats. With thrombin or 846.0 pmol/L angiotensin II prostacyclin production was significantly reduced by 18 to 55% in copper-marginal and copper-deficient rats. Copper-dependent superoxide dismutase activity was significantly depressed by 30 and 57% in aortae of copper-marginal and copper-deficient rats. Lipid peroxidation, estimated by the thiobarbituric acid test, was significantly increased by 85% in copper-deficient rats, with a nonsignificant 40% increase in aortae from copper-marginal rats. The results suggest that the decreases in aortic prostacyclin production in aortae from both copper-deficient and copper-marginal rats are associated, in a dose-dependent manner, with copper-dependent superoxide dismutase depression and increases in aortic lipid peroxidation.
Nelson
S K
SK
Department of Food Science and Human Nutrition, Colorado State University, Fort Collins 80523.
Huang
C J
CJ
Mathias
M M
MM
Allen
K G
KG
D000704:Analysis of Variance; D000818:Animals; D001013:Aorta, Thoracic / Q000201:enzymology / Q000378:metabolism*; D001835:Body Weight; D003300:Copper / Q000008:administration & dosage / Q000032:analysis / Q000172:deficiency*; D046508:Culture Techniques; D004032:Diet; D004305:Dose-Response Relationship, Drug; D011464:Epoprostenol / Q000096:biosynthesis*; D015227:Lipid Peroxidation; D008099:Liver / Q000737:chemistry; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013482:Superoxide Dismutase / Q000378:metabolism*
D003300:Copper; D011464:Epoprostenol; D013482:Superoxide Dismutase