Table 1.
LPA is the main platelet shape change-inducing lipid in mox-LDL and atherosclerotic plaques
| Lipid fractions | Shape change; %
|
||
|---|---|---|---|
| nat-LDL | mox-LDL | Plaques | |
| Chloroform extract | |||
| Neutral lipids | 3 ± 1 | 2 ± 1 | 4 ± 2 |
| Sphingomyelin | 0 | 0 | 0 |
| Phosphatidylcholine | 0 | 0 | 3 ± 2 |
| Phosphatidylethanolamine | 0 | 0 | 0 |
| Lysophosphatidylcholine | 2 ± 1 | 7 ± 3 | 10 ± 3 |
| Butanol extract | |||
| LPA | 13 ± 5 | 100 | 100 |
Lipids were extracted from nat-LDL, mox-LDL, and human atherosclerotic plaques by a two-step procedure and separated by TLC. Lipids equivalent to 0.1 mg of protein were added to platelet suspensions for measurement of platelet shape change. The absolute amounts of lipids that were added varied according to the different LDL preparations and plaque specimens and ranged for phospholipids in mox-LDL (in nmol): sphingomyelin, 14–40; phosphatidylcholine, 30–60; phosphatidylethanolamine, 0.2–0.8; lysophosphatidylcholine, 3–6; LPA, 0.04–0.1. The highest activity was found in the LPA fractions of mox-LDL and plaque, which were set to 100%. Data are shown as mean ± SD (n = 3).