The effect of phospholipase on membrane transport
MetadataShow full item record
This project studied the effect of membrane lipid metabolism on electrolyte transport in rat pancreatic secretory vesicles. The influence of phospholipase A2 and fatty acids on Cl" transport was characterized by the technique of ionophore-induced lysis in a defined salt solution. The data reveals a 12-fold increase in Cl” transport in response to phospholipase A2 treatment of the membranes. This suggests that granule membrane bound phospholipase A2 may regulate aspects of exocytosis during stimulus-secretion coupling. In addition, the effect of fatty acid incorporation into the vesicle membrane was determined. Direct correlations were identified between increasing fatty acid chain length and increasing electrolyte transport, as well as the degree of fatty acid saturation and electrolyte transport. These observations indicate that the membrane lipid composition can have a significant effect on the behavior of integral proteins such as ion channels. Furthermore, exocytotic exocrine Cl" transport may be regulated by membrane fluidity and the physiological activity of granule associated phospholipase A2.