Coexpression of phospholipase A2 isoforms in rat striatal astrocytes

https://doi.org/10.1016/S0304-3940(98)00262-6Get rights and content

Abstract

The expression and activity of phospholipase A2 (PLA2) isoforms were investigated in primary cultures of striatal astrocytes. The calcium ionophore A23187 together with the protein kinase C activator phorbol ester was the most potent stimulus in eliciting [3H]arachidonic acid release in the extracellular medium. Reverse transcription coupled to polymerase chain reaction (RT-PCR) showed the presence of the 85 kDa cytosolic PLA2 mRNA and the 14 kDa secretory PLA2 mRNA in untreated astrocytes. Immunoblot experiments with isoform-specific antibodies showed the presence of the cytosolic PLA2 in untreated astrocytes, while the secretory PLA2 was detected only in lipopolysaccharide-treated astrocytes. These data suggest that the two PLA2 isoforms expressed in striatal astrocytes might play different roles in cellular processes mediated by astrocytes.

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Acknowledgements

Part of this work was performed when S.S. was a recipient of an EMBO short term fellowship at INSERM U.109, Paris, France. The authors thank Dr. Piomelli for constructive criticism, Dr. R.M. Kramer (Eli Lilly, USA) and Dr. J. Ishizaki (Shionogi Research Laboratories, Japan) for providing PLA2 antibodies and sPLA2 cDNA.

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