DEVELOPMENTAL-CHANGES IN ARACHIDONIC-ACID POTENTIATION OF NMDA CURRENTS IN CORTICAL-NEURONS

DEVELOPMENTAL changes in the effects of arachidonic acid (AA) on N-met hyl-D-aspartate (NMDA) receptor-mediated currents were investigated in acutely dissociated rat cortical neurones using a whole-cell patch-cl amp method. AA potentiated peak NMDA currents (I-NMDA) in a concentrat ion-dependent manner. Potentiation by AA was greater at 2-4 postnatal days (P2-4) than at P7-8 and P15-18. Indomethacin reduced the potentia ting effect of AA only at P2-4, while caffeic acid and baicalein showe d no apparent effect, indicating that metabolites of the cyclooxygenas e pathway contribute to I-NMDA potentiation at P2-4. Staurosporine dim inished the potentiation of I-NMDA at P2-4, suggesting that protein ki nase C might ect of participate in the effect of AA. These findings su ggest that the greater potentiation of I-NMDA by AA at P2-4 has a diff erent underlying mechanism from effects seen at P7-8 or older.