Metabolism of lysophosphatidylcholine by swine platelets

Dian er Chen, Arnold A. White, M. E. Tumbleson, Grace Y. Sun

Research output: Contribution to journalArticlepeer-review

Abstract

Incubation of intact platelets from Sinclair(S-1) miniature swine with32P-labeled lysophosphatidylcholine (lyso PC) indicated the presence of an active lysophospholipase with a pH optimum of 8.0 for hydrolysis of the substrate. However, lyso PC was incorporated into the membrane phosphatidylcholines by the acyltransferase pathway upon addition of ATP, Mg++ and CoA to the platelet suspension. These results suggest that intact platelets are able to resist the cytotoxic effects of lyso PC in plasma, and the phospholipids in platelet membranes are not readily affected by the lipid environment of the plasma. The acyltransfer reaction apparently is saturated with endogenous free fatty acids since arachidonic acid added exogenously did not further enhance the incorporation activity. Neither the acyltransferase nor the lysophospholipase activity was affected by Ca++, but divalent metal ions such as Zn++ inhibited the lysophospholipase activity. Cholesterol but not cholesteryl esters elicited a biphasic effect on both enzymes, stimulating at low concentration but inhibiting at a cholesterol to lyso PC ratio greater than 1. Serum albumin inhibited the lysophospholipase but gave a small biphasic effect to the acyltransferase.

Original languageEnglish (US)
Pages (from-to)133-140
Number of pages8
JournalLipids
Volume20
Issue number3
DOIs
StatePublished - Mar 1 1985
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Organic Chemistry
  • Cell Biology

Fingerprint Dive into the research topics of 'Metabolism of lysophosphatidylcholine by swine platelets'. Together they form a unique fingerprint.

Cite this