Activity-dependent development of GABAergic synapses.

In the brain, dendrites of pyramidal neurons contain intermingled excitatory and inhibitory synapses. Synaptic connections dynamically change during development and throughout our lifetime, yet the brain can properly maintain an optimal ratio of synaptic excitation to inhibition. Despite recent advances in our understanding of the formation and refinement of excitatory glutamatergic synapses, little is known about signals that regulate inhibitory GABAergic synapse development. In this review, we discuss previous and recent insights in the cellular and molecular mechanisms that underlie GABAergic synapse formation and plasticity, with a specific focus on the key roles of synaptic activity and postsynaptic membrane molecules.