INIBIBB   05455
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE BAHIA BLANCA
Unidad Ejecutora - UE
artículos
Título:
Co-existence of Phosphatidylcholine-Specific Phospholipase C and Phospholipase D Activities in Rat Cerebral Cortex Synaptosomes
Autor/es:
MATEOS M.V.; URANGA R.M.; SALVADOR G.A.; GIUSTO N.M.
Revista:
LIPIDS
Editorial:
AOCS press
Referencias:
Año: 2006 vol. 41 p. 1 - 8
ISSN:
0024-4201
Resumen:
    ABSTRACT: DAG derived from phosphatidylcholine (PtdCho) acts as a lipid second messenger. It can be generated by the activation of phospholipase D (PLD) and the phosphatidic acid phosphohydrolase type 2 (PAP2) pathway or by a PtdCho-specific phospholipase C (PtdCho-PLC). Our purpose was to study PtdCho-PLC activity in rat cerebral cortex synaptosomes (CC Syn). DAG production was highly stimulated by detergents such as Triton X-100 and sodium deoxycholate. Ethanol and tricyclodecan-9-yl-xanthate potassium salt decreased DAG generation by 42 and 61%, respectively, at 20 min of incubation. These data demonstrate that both the PLD/PAP2 pathway and PtdCho-PLC contribute to DAG generation in CC Syn. PtdCho-PLC activity remained located mainly in the synaptosomal plasma membrane fraction. Kinetic studies showed Km and Vmax values of 350 ìM and 3.7 nmol DAG x (mg protein xh)-1, respectively. Western blot analysis with anti-PtdCho-PLC antibody showed a band of 66 KDa in CC Syn. Our results indicate the presence of a novel DAG-generating pathway in CC Syn in addition to the known PLD/PAP2 pathway.