The vascular effects of doxazosin in hypertension complicated by metabolic syndrome.
OBJECTIVE
To evaluate the vascular effects of doxazosin, an alpha-1 antagonist, in hypertensive patients with metabolic syndrome in whom the drug has previously been shown to exert beneficial metabolic actions on lipids and insulin metabolism.


METHODS
Twelve untreated non-diabetic hypertensive patients with National Cholesterol Education Program (NCEP) ATP-III defined metabolic syndrome were assigned to three-months of treatment with doxazosin (5.5 +/- 1.9 mg/die). Study variables were measured at baseline and after treatment. End-points: forearm blood flow (strain-gauge plethysmography) responses to graded intra-arterial acetylcholine and sodium nitroprusside infusion to test endothelium-dependent and independent vasodilatation respectively. Minimum forearm vascular resistance, the ratio of mean blood pressure and post-ischaemic maximal blood flow, as an index of arteriolar structure; transcapillary albumin escape rate (the 1-h decay rate of I-albumin, 6-8 microC ev) as a measure of systemic capillary permeability. Lipids, fasting and post-glucose insulin were measured at baseline and after treatment.


RESULTS
Doxazosin reduced blood pressure, augmented acetylcholine-mediated vasodilatation, decreased minimum resistance and, although not to a statistically significant extent, transvascular albumin leakage increased high-density lipoprotein (HDL) cholesterol while triglycerides and post-stimulative hyperinsulinemia decreased.


CONCLUSIONS
Doxazosin improved endothelial-mediated vasomotor function and reversed abnormal arteriolar structure in hypertensive patients with metabolic syndrome while improving lipid profile and blunting post-glucose hyperinsulinemia.
Dell'Omo
Giulia
G
Dipartimento Cardio Toracico, Universita' di Pisa, 56100 Pisa, Italy
Penno
Giuseppe
G
Pucci
Laura
L
Pellegrini
Giovanni
G
Scotti
Aurelio
A
Del Prato
Stefano
S
Pedrinelli
Roberto
R
D004305:Dose-Response Relationship, Drug; D017292:Doxazosin / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D004730:Endothelium, Vascular / Q000187:drug effects; D005500:Follow-Up Studies; D005951:Glucose Tolerance Test; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000175:diagnosis / Q000188:drug therapy*; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications* / Q000175:diagnosis*; D008875:Middle Aged; D011336:Probability; D011446:Prospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014655:Vascular Resistance / Q000187:drug effects; D014665:Vasodilator Agents / Q000627:therapeutic use*
D014665:Vasodilator Agents; D017292:Doxazosin