Bradykinin stimulates phosphodiesteratic cleavage of phosphatidylcholine in cultured endothelial cells

Vasopressin‐stimulated [3H]‐inositol phosphate and [3H]‐phosphatidylbutanol accumulation in A10 vascular smooth muscle cells

“…Furthermore, the finding that A23187-stimulated PLD activity is completely abolished by PKC inhibitor pretreatment once again emphasizes the central role PKC may play in the regulation of PLD in this cell. These findings are consistent with that obtained for ATP-stimulated endothelial cells (Martin & Michaelis, 1989), vasopressin-stimulated hepatocytes (Bocckino et al, 1987) and with a recent report that showed no effect of chelation with 10 mM EGTA upon PLD activity in AlO smooth muscle cells in culture (Welsh et al, 1990). However, in other tissues, agonist-stimulated PLD activity is reduced substantially upon extracellular calcium removal (Pai et al, 1988;Lassegue et al, 1991;.…”

Regulation of phospholipase D and primary granule secretion by P2-purinergic- and chemotactic peptide-receptor agonists is induced during granulocytic differentiation of HL-60 cells.

“…This was true regardless of whether 3H-oleic acid or 3H-glycerol was used to label cellular lipids (Table I). This contrasts with equivalent efficacies of these two agonists in stimulating PI-PLC (e.g., IP3 production) and Ca2l-mobilization (7, (18,25,30,33,37,38). It remains to be determined whether a single enzyme species is responsible for the phospholipase D activity observed under these various conditions, or whether there are multiple phospholipase D-type isozymes.…”

Proliferation-dependent changes in release of arachidonic acid from endothelial cells.

“…As arachidonic acid is selectively esterified at the sn-2 position of phospholipids, the most direct mechanism for release would be a PLA2. Alternatively, sequential action of a PLC and diglyceride lipase (7,25) or PLD, phosphatidic acid phosphatase and a diglyceride lipase (7,29) would also result in arachidonic acid release. PLC activity did not change significantly at the different growth states; conversely, we found that in vitro PLA2 activity did decrease in concert with the decreased release measured in metabolic labeling studies.…”

“…It is clear that a rise in intracellular calcium concentrations is necessary for release of arachidonic acid (7,26) and that entry of extracellular calcium is necessary for a full response in most cell types (26). There is evidence in endothelial cells that phospholipases C and D are activated concurrently with a rise in cellular calcium and PGI2 production (7,(27)(28)(29), but the contribution of these phospholipase activities to total arachidonic acid release is not known. Several groups have purified a cytoplasmic PLA2 that is selective for arachidonic acid at the sn-2 position (30)(31)(32)(33)(34)(35).…”