Effect of elevated substrates on substrate oxidation in normal and diabetic aorta.
The influence of elevated substrates (glucose, beta-hydroxybutyrate and palmitate) on the gated. The oxidation of 14C-glucose to 14CO2 was depressed in diabetic aorta at a glucose concentration of 5.6 mM in the incubation medium. The glucose oxidation in normal and mM. The oxidation of 14C-beta-hydroxybutyrate (0.5 and 1.5 mM) to 14CO2 was impaired in diabetic aorta, while the oxidation of 14C-palmitate (0.5 and 1.0 mM) to 14CO2 was unaltered. The oxidation of both substrates was concentration dependent. The glucose oxidation in normal rat aorta was reduced by addition of 3.0 and 6.0 mM of beta-hydroxybutyrate to the incubation medium, while 1.5 mM palmitate had no effect on the glucose oxidation. After incubation of normal rat aorta in MEM with glucose (20.0 mM) for 46 h the subsequently determined glucose oxidation was not influenced in comparison to the aorta incubated in 5.6 mM glucose. Incubation with 6.0 mM beta-hydroxybutyrate or 1.5 mM palmitate did not affect the aortic glucose oxidation. In rats which were infused for 24 h with glucose or beta-hydroxybutyrate to obtain diabetic levels of these substrates, there was no change in the aortic glucose oxidation compared to saline-infused controls. The present results suggests that the lowered glucose oxidation in diabetic vascular tissue is not caused by hyperglycemia or high concentrations of ketone bodies or free fatty acids in the diabetic state.
D020155:3-Hydroxybutyric Acid; D000818:Animals; D001011:Aorta / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism* / Q000494:pharmacology; D006885:Hydroxybutyrates / Q000378:metabolism* / Q000494:pharmacology; D008297:Male; D009924:Organ Culture Techniques; D010084:Oxidation-Reduction / Q000187:drug effects; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000378:metabolism* / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D006885:Hydroxybutyrates; D010169:Palmitic Acids; D019308:Palmitic Acid; D005947:Glucose; D020155:3-Hydroxybutyric Acid