The aim of this study was to investigate effects of reduced stress hormone by adrenalectomy
on rat plasma levels of lysophosphatidic acid (LPA) and other lysophospholipids. We
measured activities of lysophospholipase D (lysoPLD) in plasma and lipid phosphate
phosphatase (LPP) in blood by determining choline and inorganic phosphate, respectively.
LPA, lysophosphatidylcholine (LPC), lysophosphatidylethanolamine (LPE), lysophosphatidylinositol
(LPI), lysophosphatidylserine (LPS) and lysophosphatodylglycerol were quantified by
LC-MS/ MS. In adrenalectomized rats, plasma levels of LPA, LPE, LPS and LPI, but not
LPC, were increased. The increased level of LPA were due to decreased LPC level, increases
plasma activity of lysoPLD toward LPC and decreased LPP activity toward LPA. Daily
injections of deoxycoricosterone into rats selectively reversed increased level of
LPS. Our results suggest enzymatic mechanism for increased plasma level of LPA, and
indicate that the circulating levels of lysophospholipids including LPA in rats are
differently affected by artificial suppression of release of adrenergic hormones.
