In the central nervous system,glutamate is mainly released as excitatory neurotransmitter from neuron.During injury and many pathological conditions,huge amount of glutamate is released.Astrocytic uptake is the major mechanism to remove glutamate from the synapse.Our previous findings showed that the uptaken glutamate could be synthesized to glutamine and utilized by the TCA cycle.However,there is a lack of realization on how astrocyte recognizes neuronal-released glutamate under excitation.Here we reported that in addition to the well-known cytosolic swelling,glutamate could trigger astrocytic nuclear swelling.The nuclear swelling was independent from the cytosolic swelling.It appeared to be a direct effect of glutamate and was concentration dependent.Glutamate induced nuclear swelling may be astrocytic specific as we did not observe a similar effect in fibroblast.