Platelet-activating factor acetylhydrolase activity in red blood cell-stroma from patients with cerebral thrombosis.
Platelet-activating factor (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine, PAF) is a bioactive phospholipid and inactivated by a specific enzyme, PAF acetylhydrolase (PAF-AH). We have measured PAF-AH activity in red blood cells (RBCs) from patients with a history of cerebral thrombosis and age-matched healthy controls. The activities in 34 patients and 34 controls were 1.29 +/- 0.28 and 1.64 +/- 0.26 nmol/10(9) RBCs/min (or, 30.0 +/- 5.8 and 35.1 +/- 4.7 nmol/g protein/min) (mean +/- SD), respectively, and the difference was significant (p less than 0.001). In patients, RBC PAF-AH activity correlated positively with RBC filterability, an index of RBC deformability (r = +0.501, p less than 0.05). The RBC activity may play a role in scavenging oxidation products of membrane phospholipids. Lower RBC PAF-AH activity may predispose to ischemic diseases by disturbing microcirculatory behavior of the RBCs.
Yoshida
H
H
Department of Pathological Physiology, Hirosaki University, Japan.
Satoh
K
K
Imaizumi
T
T
Takamatsu
S
S
Hiramoto
M
M
Shoji
B
B
Takamatsu
M
M
D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000098:blood supply; D004907:Erythrocyte Deformability / Q000502:physiology; D004912:Erythrocytes / Q000201:enzymology*; D005260:Female; D006801:Humans; D002542:Intracranial Embolism and Thrombosis / Q000201:enzymology*; D008297:Male; D008833:Microcirculation / Q000502:physiology; D008875:Middle Aged; D010741:Phospholipases A / Q000097:blood*; D012016:Reference Values
D010741:Phospholipases A; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase