PREVENTION OF THE INDUCED SYNTHESIS AND SECRETION OF GROUP-II PHOSPHOLIPASE-A2 BY BREFELDIN-A

Brefeldin A (BFA) has previously been shown to block protein secretion and to cause dismantling of the Golgi cisternae in many cultured cell lines. BFA was found to prevent the induced synthesis and secretion o f 14 kDa group II phospholipase A2 (PLA2) in rat mesangial cells. Furt hermore, BFA inhibited total protein synthesis although PLA2 appeared to be more sensitive to the effect of this compound than total protein synthesis assessed by amino acid incorporation. BFA was unable to blo ck protein synthesis or PLA2 activity in the cell completely but secre tion of enzymatic activity and PLA2 protein into the cell culture medi a was totally inhibited.