Dynamic imaging of AMPA receptor trafficking in vitro and in vivo.

Modulation of synaptic strength through trafficking of AMPA receptors is a fundamental mechanism underlying synaptic plasticity and has been shown to be an important process in higher brain functions such as learning and memory. Many studies have used live time-lapse imaging of fluorescently tagged AMPA receptors to directly monitor their membrane trafficking in the basal state as well as during synaptic plasticity. While most of these studies are performed in vitro using neuronal cell cultures, in the past years technological advances have enabled the imaging of synaptic proteins in vivo in intact organisms. This has allowed for visualization of synaptic plasticity on a molecular level in living and behaving animals. Here, we discuss key studies and approaches using dynamic imaging to visualize AMPA receptor trafficking in vitro as well as imaging synaptic proteins, including AMPA receptors, in vivo.