Roles of cytosolic phospholipase A(2) and platelet-activating factor receptor in the Ca-induced biosynthesis of PAF.
Casein-elicited peritoneal exudate cells (PEC), mainly consisted of neutrophils, were collected from platelet-activating factor receptor-knock-out (PAFR-KO), cytosolic phospholipase A(2) knock-out (cPLA(2)-KO), and wild-type (WT) mice. After stimulation of PEC with calcium ionophore A 23187, PAF levels were measured by radio-ligand binding assay using receptor-rich membrane fraction prepared from the PAF receptor transgenic mice. We found that the level of PAF production by PEC was not different between WT and PAFR-KO mice. On the other hand, cPLA(2)-KO mice were deficient in the PAF production. These results provide the direct evidence while cPLA(2) is essential in the production of PAF, PAF receptor deficiency has little effect on the PAF production.
Shindou
H
H
Department of Biochemistry and Molecular Biology, University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Ishii
S
S
Uozumi
N
N
Shimizu
T
T
D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D002118:Calcium / Q000494:pharmacology*; D002452:Cell Count; D003600:Cytosol / Q000201:enzymology / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D018482:Muscle, Skeletal / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D010741:Phospholipases A / Q000378:metabolism*; D010972:Platelet Activating Factor / Q000096:biosynthesis*; D010980:Platelet Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled
D008565:Membrane Proteins; D010972:Platelet Activating Factor; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; C039351:platelet activating factor receptor; D010741:Phospholipases A; D002118:Calcium