Oral glucose loading attenuates endothelial function in normal individual.
BACKGROUND
We evaluated the relationship between glucose fluctuation and vascular endothelial function.


METHODS
We recruited 25 healthy individuals with no family history of diabetes (14 subjects and 11 controls). Brachial artery flow-mediated dilation (FMD) and elapsed time when the after-hyperaemia maximum brachial artery diameter is reached; the peak times (PT) of each study subject were measured before and at 60, 120, and 180 min after 75-g oral glucose loading. FMD and PT of controls were measured for four consecutive hours in the fasting state from morning. Also, brachial-ankle pulse wave velocity (baPWV) of each subject was measured at 180 min after 75-g oral glucose loading.


RESULTS
Flow-mediated dilation of the study subjects was significantly lower at 60, 120 and 180 min than at pre-load, and significantly lower than that of the controls at 60 and 120 min, but not significantly different at 0 and 180 min. There was no significant difference between the PT of the subjects and the controls during 75-g oral glucose loading. In contrast, the PT of the subjects was significantly shorter than that of the controls at 120 and 180 min, but showed no significant difference at 0 and 60 min. Moreover, baPWV had no significant relationship with FMD.


CONCLUSIONS
Our study showed that oral glucose loading attenuates FMD and shortens elapsed time at the maximum after-hyperaemia diameter, and the effect of glucose fluctuation on atherosclerosis in individuals with normal glucose tolerance remains despite only the attenuation of endothelial function.
Department of Internal Medicine (Divisions of Cardiology, Hepatology, Geriatrics and Integrated Medicine), Nippon Medical School, Tokyo, Japan.
Kentaro
K
Watanabe
Kenzo
K
Oba
Tatsuya
T
Suzuki
Motoshi
M
Ouchi
Kazunari
K
Suzuki
Shoko
S
Futami-Suda
Kenichi
K
Sekimizu
Naofumi
N
Yamamoto
Hiroshi
H
Nakano
D000284:Administration, Oral; D000328:Adult; D001786:Blood Glucose / Q000032:analysis*; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D016022:Case-Control Studies; D004730:Endothelium, Vascular / Q000502:physiology*; D005260:Female; D005947:Glucose / Q000008:administration & dosage*; D005951:Glucose Tolerance Test / Q000379:methods; D006801:Humans; D007328:Insulin / Q000032:analysis*; D008297:Male; D019518:Postprandial Period / Q000502:physiology; D014463:Ultrasonography
D001786:Blood Glucose; D007328:Insulin; D005947:Glucose