XDH and endothelial dysfunction: The increase in blood pressure in hyperuricemic individuals is predominantly attributed to oxidative stress and intracellular urate activity, mediated chiefly by xanthine oxidoreductase (XOR).299 Uric acid deposition-induced inflammation, resulting in endothelial dysfunction and vascular damage (referred to as vascular gout), can occur at serum uric acid levels exceeding 6.5 mg/dL.