Close relationship between sympathetic activation and coronary microvascular dysfunction during acute hyperglycemia in subjects with atherosclerotic risk factors.
BACKGROUND
The effect of acute hyperglycemia (AHG) during the oral glucose tolerance test (OGTT) on coronary microvascular function was evaluated, as well as the associations among the changes in coronary microvascular function, oxidative stress, and sympathetic tone.


RESULTS
Transthoracic Doppler echocardiography and OGTT were performed in 24 subjects with atherosclerotic risk factors (61+/-9 years). The coronary flow velocity before and during the infusion of adenosine (CFV(hyp)), plasma levels of thiobarbituric acid-reactive substances (TBARS), and the low-frequency/high-frequency power (LF/HF) ratio yielded by power spectral analysis of heart rate variability were measured before and at 1 h during 75-g OGTT. AHG significantly decreased the CFV(hyp), and increased the TBARS and LF/HF. Multiple linear regression analysis revealed that the percent changes in the CFV(hyp) were significantly associated with the percent changes in the LF/HF ratio (beta=-0.43, p<0.05).


CONCLUSIONS
In subjects with atherosclerotic risk factors who may be considered likely to have atherosclerotic arterial damage, AHG seems to induce concomitant coronary microvascular dysfunction, increased oxidative stress, and sympathetic activation. Coronary microvascular dysfunction, therefore, appears to be closely related to sympathetic activation.
Takei
Yasuyoshi
Y
Second Department of Internal Medicine, Tokyo Medical University, Japan.
Tomiyama
Hirofumi
H
Tanaka
Nobuhiro
N
Yamashina
Akira
A
D000208:Acute Disease; D000368:Aged; D003324:Coronary Artery Disease / Q000503:physiopathology*; D003331:Coronary Vessels / Q000294:innervation* / Q000503:physiopathology*; D005260:Female; D005951:Glucose Tolerance Test; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006943:Hyperglycemia / Q000503:physiopathology*; D016014:Linear Models; D008297:Male; D008833:Microcirculation / Q000502:physiology; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology; D012039:Regional Blood Flow / Q000502:physiology; D012307:Risk Factors; D013564:Sympathetic Nervous System / Q000502:physiology*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D017392:Thiobarbituric Acid Reactive Substances