Adrenoreceptors, endothelial function, and lipid profile: effects of atenolol, doxazosin, and carvedilol.
BACKGROUND
The use of effective blood-pressure-lowering drugs has not achieved the expected reduction in the incidence of ischaemic heart disease in hypertensive patients. This study examined the cardiovascular effects of adrenergic blockade (alpha or beta, or both) and its effect on the fibrinolytic response of the endothelium to anoxia and lipoprotein metabolism in 78 hypertensive patients with ischaemic heart disease.


METHODS
All patients had stable angina on positive exercise testing and silent ischaemia on 24 h Holter monitoring at baseline and 6 months after effective blood-pressure-lowering treatment with the selective beta-blocker atenolol, the alpha 1-inhibitor doxazosin, or the dual-action drug carvedilol.


RESULTS
Atenolol increased the effort time (P < 0.05), total ischaemia (P < 0.05), and the number of ischaemic episodes (P < 0.05). It reduced the lipoprotein ratio (P < 0.05) but did not modify the fibrinolytic activity of the endothelium. Doxazosin increased the fibrinolytic index (ratio of plasminogen activator to its main inhibitor) before (P < 0.05) and after anoxia (P < 0.0001) and the lipoprotein ratio (P < 0.001), without an anti-ischaemic effect. Carvedilol increased the effort time (P < 0.05), reducing total ischaemia (P < 0.05), the number of ischaemic episodes (P < 0.01), and increasing the post-anoxia fibrinolytic index (P < 0.05) without modifying the lipid profile.


CONCLUSIONS
At antihypertensive equipotent doses, the inhibition of alpha 1-receptors improves the endothelial fibrinolytic activity and the lipid profile. beta-Blockade has an anti-ischaemic action, but reduces the lipoprotein ratio (ApoA/ApoB) and does not improve endothelial fibrinolytic activity.
González Maqueda
I
I
La Paz Hospital, Madrid, Spain.
D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001262:Atenolol / Q000494:pharmacology / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D002227:Carbazoles / Q000494:pharmacology / Q000627:therapeutic use*; D000077261:Carvedilol; D002784:Cholesterol / Q000097:blood; D017292:Doxazosin / Q000494:pharmacology / Q000627:therapeutic use*; D015716:Electrocardiography, Ambulatory / Q000187:drug effects; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology; D016552:Ergometry / Q000187:drug effects; D005260:Female; D005342:Fibrinolysis; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D008074:Lipoproteins / Q000097:blood / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000097:blood / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D011412:Propanolamines / Q000494:pharmacology / Q000627:therapeutic use*; D010959:Tissue Plasminogen Activator / Q000187:drug effects / Q000378:metabolism; D016896:Treatment Outcome; D014280:Triglycerides / Q000097:blood
D000959:Antihypertensive Agents; D002227:Carbazoles; D008074:Lipoproteins; D011412:Propanolamines; D014280:Triglycerides; D000077261:Carvedilol; D001262:Atenolol; D002784:Cholesterol; D010959:Tissue Plasminogen Activator; D017292:Doxazosin