ABSTRACT
Objective In order to investigate the synaptic plasticity in dentate gyrus after seizures and axonal and dendrtic sprout- ing induced by KA administration. Methods The density of synapses, the curvature forms of synaptic interface were studied under electron microscope. Results 1 .The density of the synapse is decreased obviously 3 days after KA injection, while the density of synapses is increased to control level 7 days after KA injection. 2. Compare with the curvation forms of synaptic interface of control animals and 3days after KA administration animals, the amount of smile synapses is significantly decresed and the amount of frown synapses is significantly increased in the moleculous layer of dentate gyrus 7 days after KA injection. Conclusions 1 .This result demonstrates that the axonal and dendritic sprouting of dentate granule cells is functional. 2. The increase of frown synapse is related to the release of glutamate of sprouting mossy fibers.