A possible role for phospholipases in the release of neurotransmitter amino acids from ischemic rat cerebral cortex

The involvement of phospholipases in ischemia-evoked release of aspartate, glutamate, glycine, and GABA from the cerebral cortex was studied in a four vessel occlusion rat model of cerebral ischemia/reperfusion. In comparison with the control group, the phospholipase A2 inhibitor mepacrine significantly decreased the ischemia-evoked efflux of transmitter amino acids into cortical superfusates. Direct application of phospholipases A2 or C to the cerebral cortex of non-ischemic animals resulted in a significant increase in amino acid levels. These results suggest that neurotransmitter release following cerebral ischemia may involve phospholipase induced plasma membrane disruption.