Genes encoding multiple forms of phospholipase A 2 are expressed in rat brain

Abstract

The polymerase chain reaction was utilized to determine which of six cloned phospholipase A 2 (PLA 2) messenger RNAs (mRNAs), encoding four distinct low molecular weight forms of secretory PLA 2 (PLA 2-IB, PLA 2-IIA, PLA 2-IIC and PLA 2-V), a calcium-dependent high molecular weight PLA 2 (PLA 2-IV, cPLA 2) and a calcium-independent high molecular weight PLA 2 (PLA 2-VI, iPLA 2), were expressed in different regions of rat brain and in a number of peripheral tissues. Pancreatic PLA 2-IB mRNA was not expressed in the brain. PLA 2-IIA, PLA 2-IV and PLA 2-VI mRNAs appeared to be ubiquitously expressed in brain, with relatively similar levels detected in all regions. PLA 2-IIC mRNA was expressed in all brain regions but not in any of the peripheral tissues studied. PLA 2-V mRNA was found at low levels in most areas of the brain, but at very high levels in the hippocampus. These results indicate that mammalian brain has the potential to express multiple isoforms of PLA 2 which could be important given the potential role of these enzyme activities in ischaemic damage and in the regulation of synaptic plasticity.