title: Effect of acute hyperglycemia on potassium (86Rb+) permeability and plasma lipid peroxidation in subjects with normal glucose tolerance.
abstract: Hyperglycemia is likely to be one of the important determinants of ion transport as it is known to induce oxidative stress and may thus enhance non-specific permeability of membranes. The aim of the present study was to evaluate the effects of an acute increase in glycemia on 86Rb+ (a marker for K+) influx and lipid peroxidation. We evaluated the 75-g oral glucose tolerance test (OGTT)-induced modification on 86Rb+ influx and plasma lipid peroxidation in 20 subjects with normal glucose tolerance (NGT). After 2-hour glucose loading, the levels of passive 86Rb+ influx and plasma lipid peroxidation were significantly increased, whereas the active influx of 86Rb+ was unchanged. The total and passive influx of 86Rb+ into erythrocytes was significantly correlated with the level of plasma lipid peroxidation. This study demonstrates that acute hyperglycemia induces an increase in the passive influx of 86Rb+ in subjects with NGT, suggesting that acute hyperglycemia may produce an oxidative stress in plasma. These changes may be among the earliest changes occurring in response to hyperglycemia.
authors.affiliation: Department of Medical Biology Cerrahpasa Medical Faculty, Istanbul University, Turkey. mgguven@istanbul.edu.tr
authors.forename: M
authors.initials: M
authors.lastname: Güven
authors.forename: I
authors.initials: I
authors.lastname: Onaran
authors.forename: T
authors.initials: T
authors.lastname: Ulutin
authors.forename: G
authors.initials: G
authors.lastname: Sultuybek
authors.forename: H
authors.initials: H
authors.lastname: Hatemi
mesh_terms: D000208:Acute Disease; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005951:Glucose Tolerance Test; D006706:Homeostasis; D006801:Humans; D006943:Hyperglycemia / Q000097:blood*; D007328:Insulin / Q000097:blood; D015227:Lipid Peroxidation / Q000502:physiology*; D008055:Lipids / Q000097:blood; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D018384:Oxidative Stress / Q000502:physiology; D011188:Potassium / Q000097:blood*; D012414:Rubidium Radioisotopes
chemical_list: D001786:Blood Glucose; D007328:Insulin; D008055:Lipids; D012414:Rubidium Radioisotopes; D008315:Malondialdehyde; D011188:Potassium