Cell-surface receptors regulate hydrolysis of cellular phospholipids that are catalyzed by different classes of phosphohpases having distinct specificities. Depending on cell-type and stimulus, multiple lipid signaling pathways are recruited to allow for the physiological response of the cell to be manifested. Thus, receptors can be coupled to activation of the inositol lipid-specific phospholipase C (PLC), phosphohpase A2 (PLA2 ) and phosphohpase D (PLD) and give rise to multiple second messengers and bioactive metabolites.
