ABSTRACT
The effect of neuroleptics on phospholipase A2 (PLA2) activity in rat brain plasma membranes was studied. Chlorpromazine (10 mg/kg), fluphenazine (5 mg/kg), thioridazine (5 mg/kg), trifluoperazine (5 mg/kg), haloperidol (2 mg/kg), and sulpiride (100 mg/kg) were administered to rats intraperitoneally as a single dose or long-term treatment (4 weeks). The PLA2 activity was determined 24, 48, and 72 h after the last injection of a drug. The enzyme activity was decreased after a single or 4-week administration of chlorpromazine, trifluoperazine, haloperidol, and sulpiride. Fluphenazine and thioridazine caused an increase of PLA2 activity in rat brain both after a single dose and long-term administration. For the first time it was shown that neuroleptics cannot only inhibit but also increase, PLA2 activity. Elucidation of this fact requires further studies.
