Effects of low-dose aspirin on endothelial function in hypertensive patients.
BACKGROUND
It has been reported that administration of low-dose aspirin significantly reduces the frequency of major cardiovascular events in patients with hypertension and coronary artery disease. It is generally considered that the preventative effects of long-term aspirin administration on major cardiovascular events are due to the inhibition of platelet aggregation.


OBJECTIVE
It is not known whether administration of low-dose aspirin restores endothelium-dependent vasodilatation, and this study was undertaken to prove or disprove this question in patients with hypertension.


METHODS
Flow-mediated endothelium-dependent dilatation and glyceryl trinitrate-induced endothelium-independent dilatation were investigated in 18 hypertensive patients and 10 normotensive control subjects. In the hypertensive patients, flow-mediated dilatation was investigated and cyclic guanosine monophosphate plasma (cGMP) was measured before and at 8 weeks after the administration of 162 mg of aspirin.


RESULTS
Flow-mediated dilatation before aspirin administration was more reduced in the hypertensive patients than in the control subjects (6.4+/-2.0% vs. 11.3+/-2.3%, p <0.0001). Glyceryl trinitrate-induced dilatation before aspirin administration was similar in hypertensive patients and control subjects. Flow-mediated dilatation after aspirin administration was improved compared with that before aspirin administration (10.4+/-3.5% vs. 6.4+/-2.0%, p<0.0004). The cGMP product after aspirin administration was significantly higher than that before aspirin administration.


CONCLUSIONS
Administration of low-dose aspirin may restore the endothelium-dependent vasodilatation in hypertensive patients. Furthermore, increased nitric oxide production may play a partial role in the improvement in endothelial function induced by administration of low-dose aspirin.
Monobe
H
H
Department of Cardiovascular Medicine, Okayama University Medical School, Japan.
Yamanari
H
H
Nakamura
K
K
Ohe
T
T
D000368:Aged; D001241:Aspirin / Q000008:administration & dosage / Q000494:pharmacology*; D001810:Blood Volume / Q000187:drug effects / Q000502:physiology; D016022:Case-Control Studies; D006152:Cyclic GMP / Q000097:blood; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology; D014664:Vasodilation / Q000502:physiology*; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000494:pharmacology*
D014665:Vasodilator Agents; D006152:Cyclic GMP; D001241:Aspirin