Possible Interaction: Phosphatidic Acid and Calcium Supplement

“There is increasing evidence that phosphatidic acid acts as an intracellular signalling molecule regulating release of calcium from intracellular stores, sphingosine kinase and protein kinase C activation and membrane budding.”

“Concomitantly, a loss of acidic phosphate groups due to a formation of phosphate groups with bound calcium is observed.”

“Conversely, a first exposure to PA only partially inhibited the CD3- or ionomycin-induced internal release of calcium , suggesting either a rapid restoration of the PA-sensitive stores, or a contribution of other mediators, such as IP3, in the CD3 activation pathway.”

“ Phosphatidic acid , however, did cause an elevation in intracellular calcium and is consistent with its putative role as an ionophore in other non-excitable exocrine tissues.”

“ Calcium produced significant decrements in 32P incorporation into phosphatidylinositol, di- and triphosphatidylinositol and an increase into phosphatidic acid.”

“It is possible that calcium , PTH or both affects phospholipid turnover of RBC and results in production of ionophoric compounds such as phosphatidic acid which in turn allows calcium movement.”

“ Phosphatidic acid at a molar ratio of 20 mole percent produces a marked decrease in Km for phospholipid and for calcium (Km ∼ 20 μM).”

“Thus, the specific activity of the 32P‐phosphatidic acid increased four‐ to five‐fold in response to calcium.”

“Among the phospholipids tested, cardiolipin and phosphatidic acid exerted a significant increase of calcium uptake by platelets.”

“At 10--60 micrograms/ml phosphatidic acid caused a concentration dependent release of calcium from the membrane fraction.”

“ PtdA has been variously reported to activate the inositol lipid cascade, alter membrane permeability to calcium and to release calcium from intracellular stores (1,2).”