Role of Calcium-Permeable AMPARs in Synaptic Tagging and Capture in the Rodent Hippocampus

Long-term potentiation (LTP) at hippocampal synapses is classically triggered by the synaptic activation of NMDA receptors (NMDARs) and is expressed, at least in part, by an increase in the number of calcium-impermeable (CI)-AMPARs (CI-AMPARs). NMDARs confer “Hebbian” properties to this form of synaptic plasticity, including input specificity to the synapses receiving the induction stimulus. Synaptic tagging and capture (STC) is an important form of metaplasticity, that is, by definition, heterosynaptic in nature. As described in detail elsewhere in this volume, STC involves a “tag” to mark activated synapses and a “capture” mechanism to enable “tagged synapses” to induce a protein synthesis-dependent form of LTP. Here, we summarize our recent work that suggests calcium-permeable (CP)-AMPARs (CP-AMPARs) serve as the synaptic tag and also help trigger the de novo protein synthesis, by which synapses are “captured.”