title: Ascorbic acid blocks hyperglycemic impairment of endothelial function in adolescents with type 1 diabetes.
abstract: OBJECTIVE
  To determine whether acute ascorbic acid infusions alter the effect of hyperglycemia on endothelial function in adolescents with type 1 diabetes.
  
  
  METHODS
  The forearm blood flow (FBF) reactive hyperemic response to 5 min of upper arm occlusion was studied in eight adolescents with type 1 diabetes during euglycemic and hyperglycemic insulin clamp (40 mU/m2/min) with and without ascorbic acid infusion (3 mg/min).
  
  
  RESULTS
  The ratio of post- to preocclusion FBF decreased during hyperglycemia without ascorbic acid (p = 0.013), but did not change during hyperglycemia with ascorbic acid. The changes during hyperglycemia were different between the two studies (p = 0.038). Similar results were found when the percent change in forearm vascular resistance following occlusion was assessed.
  
  
  CONCLUSIONS
  These results indicate that antioxidant treatment with ascorbic acid blocks acute hyperglycemic impairment of endothelial function in adolescents with type 1 diabetes.
authors.affiliation: Division of Pediatric Endocrinology, Metabolism and Diabetes, Department of Pediatrics, The Clinical Research Center of The Ohio State University College of Medicine and Public Health, Columbus, OH 43205, USA. Roff.Hoffman@nationwidechildrens.org
authors.forename: Robert P
authors.initials: RP
authors.lastname: Hoffman
authors.forename: Amanda S
authors.initials: AS
authors.lastname: Dye
authors.forename: John A
authors.initials: JA
authors.lastname: Bauer
mesh_terms: D000293:Adolescent; D000975:Antioxidants / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000008:administration & dosage*; D001783:Blood Flow Velocity; D003250:Constriction; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D004727:Endothelium / Q000187:drug effects / Q000503:physiopathology*; D005260:Female; D005542:Forearm / Q000098:blood supply; D015309:Glucose Clamp Technique; D006801:Humans; D006940:Hyperemia / Q000209:etiology / Q000503:physiopathology; D006943:Hyperglycemia / Q000150:complications*; D007328:Insulin / Q000097:blood; D008297:Male; D014664:Vasodilation / Q000502:physiology
chemical_list: D000975:Antioxidants; D007328:Insulin; D001205:Ascorbic Acid