Abstract
Robust entry of calcium ion is initiated locally at synapses upon receipt of packets of glutamate released from presynaptic terminals. This event is thought to trigger stimulation of a variety of neuronal signaling pathways that are critical in associating synaptic events with higher cognitive functions. Activation of synaptic CaMKII has been shown to play a significant role in increasing AMPA current density at postsynaptic sides. Here we show that other Ca2+-dependent signals are induced in parallel to facilitate signaling from synapse-to-nucleus and from synapse-to-actin cytoskeleton. Together, an ensemble of Ca2+-mediated biochemical switches may confer bimodal stability to synaptic signaling events, thereby enabling efficient storage of information both at the synaptic as well as at cellular levels. [Jpn J Physiol 54 Suppl:S16 (2004)]
