Effects of lactate/pyruvate on synaptic plasticity in the hippocampal dentate gyrus

The present study was undertaken to investigate whether monocarboxylates (lactate and pyruvate) can support synaptic plasticity. As an index of synaptic activity, population spikes (PS) were recorded in the hippocampal dentate gyrus. Replacement of glucose with monocarboxylates maintained PS after transient depression, and supported a similar degree of paired-pulse facilitation (PPF). Monocarboxylates-supported long-term potentiation (LTP), but the degree of enhancement was less than that of glucose-supported PS. Monocarboxylates failed to support long-term depression (LTD). These results indicate that monocarboxylates could serve as sufficient substrates for PPF, and that they could also support LTP but with less efficiency than glucose.