Acetylcholine Effects on STDP Induced on Spatial and Non-spatial Information in Dentate Gyrus

Abstract

Spatial and non-spatial information, coming from medial perforant path (MPP) and lateral perforant path (LPP), respectively, is considered to be integrated on granule cell in dentate gyrus (DG) to play an important role in learning and memory. At both connected sites on dendrite, the phenomenon of learning and memory of spike timing-dependent plasticity (STDP) is known to be induced. Meanwhile, acetylcholine (ACh) is released from cholinergic terminals in DG when attentional processes are paid. And there are reports that ACh enhanced STDP in CA1 area. In order to investigate the ACh effects on STDP and its mechanism in DG, STDP-inducing protocol was applied to measure STDP on MPP or LPP in the presence of eserine, furthermore, the changes in baseline amplitude during the STDP protocol were investigated. As the results, STDPs at both sites were enhanced if ACh receptors were activated and then clarified that the baseline amplitude was one of the factors for the enhancement on MPP. These findings suggest that spatial and non-spatial information is strengthened in learning and memory if attentional processes are paid, but the underlain mechanisms are different.