Coexpression of phospholipase A2 isoforms in rat striatal astrocytes.
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.
Zanassi
P
P
Istituto di Farmacologia della Facoltà di Farmacia, Università di Pavia, Italy.
Paolillo
M
M
Schinelli
S
S
D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism; D001253:Astrocytes / Q000187:drug effects / Q000201:enzymology*; D000001:Calcimycin / Q000494:pharmacology; D003342:Corpus Striatum / Q000201:enzymology*; D004789:Enzyme Activation / Q000187:drug effects; D004790:Enzyme Induction / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D007527:Isoenzymes / Q000096:biosynthesis* / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics; D010741:Phospholipases A / Q000096:biosynthesis* / Q000235:genetics; D054467:Phospholipases A2; D016133:Polymerase Chain Reaction; D011493:Protein Kinase C / Q000378:metabolism; D011796:Quinacrine / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D004791:Enzyme Inhibitors; D007476:Ionophores; D007527:Isoenzymes; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D016718:Arachidonic Acid; D000001:Calcimycin; D011493:Protein Kinase C; D010741:Phospholipases A; D054467:Phospholipases A2; D011796:Quinacrine; D013755:Tetradecanoylphorbol Acetate