Ethanol-induced alteration in activities of cerebral phosphatidylinositol 4,5-biphosphate-specific and cytosolic phospholipase C in the brain: analysis using NG 108-15 cells and brains from ethanol-inhaled mice.
Effect of long-term exposure to ethanol (EtOH) on the phosphatidylinositol 4,5-biphosphate (PIP2)-specific and cytosolic phospholipase C (PLC) activities in neuroblastoma x glioma hybrid (NG 108-15) cells and the brains from EtOH-inhaled mice were investigated. Long-term (2 days) exposure of NG 108-15 cells to EtOH induced significant decrease in PIP2-specific PLC activity dependent on concentration and duration of exposure, although the presence of EtOH in the enzyme assay system induced no alteration in PIP2-specific PLC activity. On the other hand, cytosolic PLC activity in NG 108-15 cells significantly increased by both the long-term exposure of the cells to EtOH and the addition of EtOH into the assay system. These changes in activities of both types of PLC in NG 108-15 cells observed after EtOH exposure recovered rapidly by the removal of EtOH. Moreover, the changes in activities of PIP2-specific and cytosolic PLC in the brain of EtOH-inhaled mice were similar to those found in NG 108-15 cells. These results indicate that EtOH inhibits the activity of PIP2-specific PLC and activates cytosolic PLC in the brain. These changes in cerebral PLC activities are suggested to involve in central action of EtOH and establishment of alcohol dependence.
Katsura
M
M
Department of Pharmacology, Kyoto Prefectural University of Medicine, Japan.
Ohkuma
S
S
Chen
D Z
DZ
Kuriyama
K
K
D000280:Administration, Inhalation; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D003600:Cytosol / Q000201:enzymology; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000008:administration & dosage / Q000494:pharmacology*; D005910:Glioma; D006822:Hybrid Cells; D007700:Kinetics; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009447:Neuroblastoma; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism*; D051381:Rats; D014407:Tumor Cells, Cultured; D010738:Type C Phospholipases / Q000378:metabolism*
D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D000431:Ethanol; D010738:Type C Phospholipases