Modulation of phospholipase A2 activity in primary cultures of rat cortical neurons

In neurons, phospholipase A(2) (PLA(2)) plays a central role in the regulation of membrane phospholipid metabolism. We have addressed the pharmacological modulation of PLA(2) in primary cultures of rat cortical neurons. Inhibition curves were obtained in 4 day-in-culture neurons treated for 30 minutes with either the dual PLA(2) inhibitor methyl arachidonyl fluorophosphonate (MAFP), or the iPLA(2) inhibitor bromoenol lactone (BEL). Full inhibition was achieved with 100 and 250 mu M of MAFP, or 10 and 2 mu M of BEL. Conversely, a dose-dependent activation of PLA(2) was obtained with 10-20 mu g/ml of melitin. PLA(2) inhibition with MAFP or BEL was not acutely toxic for cultured neurons. However, sustained inhibition of the enzyme precluded the development of neurites, and resulted in long-term loss of neuronal viability. We present a model of pharmacological challenge of PLA(2) in vitro, which can be further used to address the involvement of the enzyme in neurodevelopment and neurodegeneration models.