Consumption of High Fructose and Glucose Impairs Aortic Function in Female Rats

Intake of high fructose, especially in soft drinks, has shown to contribute to variety of metabolic disorders such as diabetes and obesity. The objective of this study was to compare the effects of high glucose (HG) and high fructose (HF) (20% w/v in drinking water for 8 weeks) consumption on female rat aortic function. Endothelium-dependent vasodilation (EDV) to acetylcholine (ACh; 10-8 to 10-5M) and bradykinin (BK; 10-9 to 10-5 M) and endothelium-independent vasodilation to sodium nitroprusside (SNP; 10-9 to 10-5 M) were measured in aortic rings pre-contracted with phenylephrine (PE) or U46619. Furthermore, constrictor response curves to PE (10-8 to 10-5 M) were generated. The EDV to ACh was preserved in both HF- and HG- groups. HF ingestion, but not HG, significantly decreased maximal relaxation to BK. The potency of endothelium-independent vasodilation to SNP was augmented in aortic rings from HG group. However, HF ingestion significantly attenuated the potency of relaxation to SNP. The PE-induced contraction was not changed in HF group, but it was decreased in aortic rings from HG-fed rats. Our data suggest that an increase in the sensitivity of smooth muscle to NO may in part contribute to the decreased PE contractile responsiveness in HG group. Furthermore, a decrease in the sensitivity of vascular smooth muscle to NO along with the impaired vasodilatory responses to BK in aortas of HF-fed rats suggest that fructose ingestion may have a higher impact in inducing aortic dysfunction compared to glucose ingestion (supported by NIDCR)