Impact of black tea on forearm endothelial function De invloed van zwarte thee op de vaatfunctie

INTERVENTION: ingestion of black tea vs placebo‐tea CONDITION: Blood pressure, Hypertension, Endothelial function, , ; ; PRIMARY OUTCOME: Mean forearm blood flow response (volume change measured by venous occlusion plethysmography) to intra‐arterially administered acetylcholine (i.e. endothelium‐independent vasodilation) SECONDARY OUTCOME: Mean forearm blood flow response (volume change measured by venous occlusion plethysmography) to intra‐arterially administered sodium nitroprusside (i.e. endothelium‐dependent vasodilation); ; Mean forearm blood flow response (volume change measured by venous occlusion plethysmography) to intra‐arterially administered sodium L‐NMMA(i.e. nitric oxide‐blocker; endothelium‐dependent vasoconstriction) INCLUSION CRITERIA: Healthy subjects: ‐ Males and post‐menopausal (> 1 years) females ‐ Aged >45 and < 75 years ‐ Body mass index (BMI) between 18.0 and „T35.0 kg