Distribution of low density lipoprotein in the branch and non-branch regions of the aorta

doi:10.1016/0021-9150(92)90045-I

Atherosclerosis

Volume 97, Issue 1, November 1992, Pages 1-9

https://doi.org/10.1016/0021-9150(92)90045-I Get rights and content

Abstract

Atherosclerosis occurs focally in branch segments of the artery. Understanding why these segments are more susceptible to the development of the disease is at the root of understanding atherogenesis. We investigated accumulation of low density lipoprotein (LDL) in the branch and non-branch regions of the aorta to determine why the disease develops in branch regions. Abdominal aortas and their major branches were harvested from 36 rabbits. Rabbit LDL was prepared from whole blood and radiolabeled with ¹²⁵I. The aorta was incubated with radiolabeled LDL in the lumen at 37°C, under intraluminal pressure of 2–3 mmHg, for 1 h. Disks of 1.8 mm diameter were punched from the branch and non-branch regions of the aorta, cryosectioned and the sections counted in a gamma counter. Protein bound radioactivity was determined by TCA precipitation. LDL accumulation was highest towards the aortic intima and declined sharply towards the media. LDL accumulation at any given depth was higher in the branch than non-branch region. LDL accumulation in the intimal-medial sections was 87% higher in the branch than non-branch region. Total LDL accumulation in the branch was almost twice that in the non-branch region. Mean LDL accumulation was also greater in the branch than non-branch region. The aorta was significantly thicker at the branch. LDL distribution profiles indicate that LDL is present in a greater concentration and over a greater depth in the branch than non-branch region. The tendency of the branch region to accumulate LDL in greater amounts may explain its susceptibility to atherosclerotic lesion development.

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^☆: This work was presented at 1989 FASEB meeting.

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Research paperDistribution of low density lipoprotein in the branch and non-branch regions of the aorta☆

Abstract

Atherosclerosis

Atherosclerosis

Biochim. Biophys. Acta

J. Biomech.

Exp. Mol. Pathol.

Atherosclerosis

Atherosclerosis

Atherosclerosis

The pathogenesis of atherosclerosis - an update

N. Engl. J. Med.

Lipoprotein metabolism in the macrophage: implications for cholesterol deposition in atherosclerosis

Annu. Rev. Biochem.

Atherosclerosis research: Decades of progress

Initiation of atherosclerotic lesions in cholesterol-fed rabbits

Arteriosclerosis

Research paper
Distribution of low density lipoprotein in the branch and non-branch regions of the aorta☆