Expression and Induction of Secretory Phospholipase A Group IB in Brain

Summary Secretory phospholipases A 2 (sPLA 2 ) form a diverse family of enzymes involved in physiologicand pathologic processes. Common among all sPLA 2 is the ability to cleave acyl groups of phospholipids at 2 C of the glycerol backbone, thereby releasingfatty acid and a lysophospholipid. Several sPLA 2 have been cloned and characterized in various tissues.Furthermore, receptors have been identified. In the nervous system sPLA 2 groups IIA, IIE, IIF, V, and XII have been identified, and binding sites for sPLA 2 group IB (sPLA 2 -IB) have been found. Here, we report sPLA 2 -IB in rat and human brain as well as in neurons in primary culture. The distribution of sPLA 2 -IB seems to be mainly neuronal, with the highest abundance occurring in the cerebral cortex and hippocampus. We also find that genes encoding sPLA 2 -IB are induced by kainic acid and by electroshock-induced convulsions.Based on the present results we suggest that sPLA 2 -IB may be a neuronal intercellular signalling modulator.