Faculty Collaboration Database

Specific incorporation of 5-hydroxy-6,8,11,14-eicosatetraenoic acid into phosphatidylcholine in human endothelial cells. Biochim Biophys Acta 1986 Feb 28;875(3):569-81

Date

02/28/1986

Pubmed ID

3004591

DOI

10.1016/0005-2760(86)90079-2

Scopus ID

2-s2.0-0022510926 (requires institutional sign-in at Scopus site)   40 Citations

Abstract

The incorporation of hydroxyeicosatetraenoic acids (HETEs) into cellular lipids was studied in cultures of human umbilical vein endothelial cells. 5-[3H]HETE was incorporated into the phospholipids (8%) and neutral lipids (15.5%). The uptake was at half maximum after 15 min and reached a plateau after 1 h. The incorporation occurred mainly into phosphatidylcholine (6.3%) with minimal uptake into phosphatidylserine and phosphatidylinositol (0.6%) or phosphatidylethanolamine (1.2%). There was no uptake of 12-[3H]HETE, 15-[3H]HETE or [3H]leukotriene B4 into phospholipids. Treatment of the phosphatidylcholine fraction with phospholipase A2 released 64% of the 5-[3H]HETE with 26% remaining in the lysophosphatidylcholine fraction. This indicates that the majority of the 5-HETE was in the sn-2 position. Unlabeled 5-HETE and arachidonic acid inhibited the uptake of 5-[3H]HETE into phosphatidylcholine with an ID50 of 2.5 and 1.25 microM, respectively. Stearic acid and 15-HETE were not effective inhibitors. Histamine, which activates phospholipases, increased the uptake of 5-[3H]HETE into phosphatidylcholine by 3-fold. Both 5-[3H]HETE and 12-[3H]HETE were incorporated into the neutral lipids of the cells. Analysis of the neutral lipid fraction revealed that 5-[3H]HETE was incorporated into mono-, di- and triacylglycerols but not cholesterol esters. Incorporation of 5-HETE into cellular lipids reduced histamine- and arachidonic acid-stimulated synthesis of 6-ketoprostaglandin F1 alpha and prostaglandin E2 in a concentration-related manner. Angiotensin I converting enzyme activity was not changed. Thus, 5-HETE is incorporated specifically into phosphatidylcholine and glycerol esters of human endothelial cells and this incorporation inhibits prostaglandin synthesis in these cells.

Author List

Richards CF, Johnson AR, Campbell WB

Author

William B. Campbell PhD Professor in the Pharmacology and Toxicology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Cattle
Cells, Cultured
Chromatography, Thin Layer
Coronary Vessels
Endothelium
Histamine
Humans
Hydrolysis
Hydroxyeicosatetraenoic Acids
Lipid Metabolism
Peptidyl-Dipeptidase A
Phosphatidylcholines
Prostaglandins
Umbilical Cord