Open AccessChemoattractants stimulate degradation of methylated phospholipids and release of arachidonic acid in rabbit leukocytes.
Author(s) -
Fusao Hirata,
Barbara Corcoran,
Κ. Venκatasubramanian,
Elliott Schiffmann,
Julius Axelrod
Publication year - 1979
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.76.6.2640
Subject(s) - chemotaxis , arachidonic acid , biochemistry , phospholipase a2 , phosphatidylcholine , choline , phosphatidic acid , phospholipase , metabolism , phospholipase d , biology , phospholipid , methionine , chemistry , enzyme , receptor , amino acid , membrane
When rabbit peritoneal leukocytes were treated with chemoattractants such as fMet-Leu-Phe, an apparent decrease of [3H]methyl incorporation into the lipid fraction from L-[methyl-3H]methionine was observed. This decrease was a result of increased degradation of methylated phospholipids, not of decreased synthesis. Chemotactic peptides did not affect the metabolism of the phospholipids in which [methyl-14C]choline was incorporated. The disappearance of the [3H]methyl group was associated with the release of [1-14C]arachidonic acid from phospholipids prelabeled with these compounds. These findings suggested the activation by chemoattractants of phospholipase A2, an enzyme that removes an unsaturated fatty acid from phospholipids. The order of potency of chemoattractants for the stimulated degradation of phospholipids was in good agreement with that for chemotaxis. Mepacrine (quinacrine) and hydrocortisone inhibited and a phorbol ester enhanced both chemotaxis and phospholipase A2 activity. These results, taken together, suggest close association of the metabolism of methylated phospholipids with chemotaxis in rabbit peritoneal leukocytes.