2,3-DIPHOSPHOGLYCERIC ACID BLOCKS LONG-TERM POTENTIATION OF EXCITATORY POSTSYNAPTIC CURRENTS IN HIPPOCAMPAL CA1 NEURONS OF THE RAT

The dependence of long-term potentiation on an intact inositol 1,4,5-t risphosphate [Ins(1,4,5)P-3] metabolism was investigated with the whol e-cell voltage-clamp method in the CA1 region of hippocampal slices. T he intracellular application of 2,3-diphosphoglyceric acid (1 mM), an inhibitor of the Ins(1,4,5)P-3 5-phosphatase and of Ins(1,4,5)P-3 3-ki nase eliminated the potentiation of postsynaptic currents in pyramidal cells 30 min after paired pre- and postsynapitc activation. These dat a suggest a possible role of postsynaptic inositol 1,4-bisphosphate an d/or inositol 1,3,4,5-tetra-kisphosphate in synaptic plasticity.