Exclusion of the ACE D/I gene polymorphism as a determinant of endothelial dysfunction.
A deletion/insertion (D/I) polymorphism within the ACE gene may increase the risk of cardiovascular events through still unknown mechanisms. The latter may involve increased angiotensin II-induced NO breakdown and/or reduced agonist-mediated NO release. We therefore investigated whether the D allele of the ACE gene affects endothelium-dependent vasodilatation in mild-to-moderate primary hypertensive patients and healthy normotensive subjects. We compared in a cross-sectional study the forearm blood flow response of the 3 D/I genotypes with 5 incrementally increasing doses of the endothelium-dependent vasodilator acetylcholine (0.15, 0.45, 1.5, 4.5, and 15 microg. 100 mL(-1). min(-1)) in 142 subjects: 103 mild-to-moderate uncomplicated primary hypertensives (49.3+/-9.1 years old, 152+/-11/99+/-5 mm Hg) and 39 normotensives (44.6+/-15.3 years old, 122+/-12/78+/-6 mm Hg). We also assessed the endothelium-independent vasodilatation in the forearm, as blood flow response to 3 incrementally increasing doses of sodium nitroprusside (1, 2, and 4 microg. 100 mL(-1). min(-1)). The overall genotype distribution was II, n=10; ID, n=70; and DD, n=62. It did not differ significantly between primary hypertensives and normotensives. A significant blunting of endothelium-dependent vasodilatation in primary hypertensive patients compared with normotensive subjects (P:<0.001) was found. No effect of the DI genotype on endothelium-dependent and -independent vasodilatation was detected. Thus, these results obtained in a relatively large population do not support the contention that the D allele is associated with a blunting of either stimulated endothelial NO or donated NO responses in both mild-to-moderate primary hypertensive patients and normotensive subjects.
Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy. gprossi@ux1.unipd.it
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Rossi
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Virdis
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Ghiadoni
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Albertin
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Sudano
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Salvetti
D000109:Acetylcholine / Q000494:pharmacology; D000328:Adult; D000483:Alleles; D000704:Analysis of Variance; D004247:DNA / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology*; D005260:Female; D005542:Forearm / Q000098:blood supply; D017353:Gene Deletion; D005838:Genotype; D006801:Humans; D006973:Hypertension / Q000235:genetics / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D016254:Mutagenesis, Insertional; D009599:Nitroprusside / Q000494:pharmacology; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011110:Polymorphism, Genetic; D012039:Regional Blood Flow / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000494:pharmacology
D014665:Vasodilator Agents; D009599:Nitroprusside; D004247:DNA; D007703:Peptidyl-Dipeptidase A; D000109:Acetylcholine