Dairy Cheese Ingestion Does Not Improve Acute Sodium-Induced Cutaneous Microvascular Dysfunction through Arginase or Inducible Nitric Oxide Synthase Mechanisms

Epidemiological studies suggest that chronic dairy consumption is associated with improved cardiovascular health; alternately high dietary sodium (Na) ingestion is associated with increased cardiovascular disease risk. Natural cheeses are often high in sodium, thus increasing dairy cheese intake may increase dietary Na intake. We recently demonstrated that single-meal cheese consumption ameliorates Na-induced impairments in nitric oxide (NO)-dependent vasodilation through ascorbate sensitive mechanisms. However, the role of additional inflammatory mediators sensitive to the non-specific antioxidant ascorbate, including arginase and inducible NO synthase (iNOS), is unknown. We hypothesized that local inhibition of arginase or iNOS would improve NO-dependent vasodilation following Na ingestion from non-dairy sources but not Na ingestion from dairy-based cheese. On 5 separate visits, 14 subjects (61±2 yrs) consumed 85 g natural cheddar cheese (560 mg Na), 85 g soy cheese (560 mg Na), 65 g pretzels (560 mg Na...