Risk factors of atherosclerosis and saphenous vein endothelial function

Area of Science:

• Vascular Biology
• Cardiovascular Research
• Endothelial Function

Background:

• Impaired vasomotor function is implicated in atherosclerosis pathophysiology.
• Endothelial dysfunction may affect bypass graft patency.
• Investigated atherosclerosis risk factors' influence on saphenous vein endothelial function in cardiovascular disease patients.

Purpose of the Study:

• To evaluate the in vitro effect of atherosclerosis risk factors on saphenous vein endothelial function.
• To assess the contractile and relaxant responses of saphenous veins to various vasoactive agents.

Main Methods:

• Studied 45 saphenous vein rings (intact and denuded endothelium).
• Administered norepinephrine (NE), acetylcholine (Ach), histamine (H), and serotonin (5-HT).
• Analyzed responses in relation to patient risk factors (diabetes, smoking, hypertension).

Main Results:

• Norepinephrine caused increased contraction in diabetics, smokers, and hypertensive patients.
• Acetylcholine response varied; relaxation was reduced in hypertensive and diabetic patients.
• Histamine induced relaxation then contraction, with greater contraction in diabetics.
• Serotonin caused contraction, unaffected by endothelial removal.
• Evidence suggests endothelium-derived contracting factor (EDCF) release.

Conclusions:

• Saphenous veins can secrete a contracting factor, particularly in patients with atherosclerosis risk factors and diabetes.
• Mechanisms regulating the balance of endothelial relaxing and contracting factors require further investigation.
• The source of vasoconstrictor substances from endothelial cells needs elucidation.