Single LDL Apheresis Improves Endothelium-Dependent Vasodilatation in Hypercholesterolemic Humans

• Published in: Circulation (New York, N.Y.) Vol. 95; no. 1; pp. 76 - 82
• Main Authors: Tamai, Osamu, Matsuoka, Hidehiro, Itabe, Hiroyuki, Wada, Yoshifumi, Kohno, Keisuke, Imaizumi, Tsutomu
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott Williams & Wilkins 07.01.1997; American Heart Association, Inc
• Subjects: Acetylcholine - pharmacology; Adult; Aged; Biological and medical sciences; Blood Component Removal; Cholesterol, LDL - blood; Disorders of blood lipids. Hyperlipoproteinemia; Endothelium, Vascular - physiopathology; Female; Forearm - blood supply; Humans; Hypercholesterolemia - blood; Hypercholesterolemia - physiopathology; Hypercholesterolemia - therapy; Male; Medical sciences; Metabolic diseases; Middle Aged; Myocardial Ischemia - etiology; Nitric Oxide - metabolism; Nitroprusside - pharmacology; Vasodilation - drug effects; Human; Apheresis; Metabolic diseases; Exploration; Lipids; Hyperlipoproteinemia; Blood flow; Endothelium; Lipoprotein LDL; Forearm; Hypercholesterolemia; Treatment; Dyslipemia
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/01.CIR.95.1.76

Background Although long-term lipid-lowering therapy improves endothelium-dependent vasodilatation in humans, it remains unknown whether the short-term removal of LDL per se ameliorates endothelial dysfunction. Methods and Results To examine the effects of a single session of LDL apheresis on endothelial function in patients with hypercholesterolemia, we measured forearm blood flow (FBF) by strain-gauge plethysmography before and after single LDL apheresis while infusing acetylcholine (ACh; 4 to 24 μg/min) and sodium nitroprusside (SNP; 0.2 to 1.2 μg/min). The single session of LDL apheresis reduced total LDL (from 142.2±15.0 to 32.6±5.0 mg/mL, P <.0005) and oxidized LDL (from 111.6±22.8 to 30.0±5.4 ng/mL, P <.005). Although ACh and SNP increased FBF dose-dependently before and after LDL apheresis, the endothelium-dependent vasodilatation responses to ACh were significantly augmented ( P <.01) after the single session of LDL apheresis without changes in the endothelium-independent vasodilatation responses to SNP. The plasma levels of total and oxidized LDL correlated with the degree of ACh-induced vasodilatation. Furthermore, the local production of nitrate/nitrite, metabolites of NO, during ACh infusion was significantly ( P <.05) augmented by LDL apheresis, and there was a significant correlation between the degree of ACh-induced vasodilatation and the production in nitrate/nitrite ( r =.99, P <.0005). Conclusions We demonstrated that even a single session of LDL apheresis with the reduction of total LDL and oxidized LDL improved endothelial function. Our results suggest that total LDL and/or oxidized LDL may directly impair endothelial function in the human forearm vessel.