[Morphology and differentially expressed proteins in hippocampus of mesial temporal lobe epilepsy model of immature rats induced by pilocarpine].

OBJECTIVE

To examine the changes of morphology and differentially expressed proteins in hippocampus at the latent stage of chronic mesial temporal lobe epilepsy (MTLE) in immature rats, and to explore the global mechanism of chronic MTLE at a new point.

METHODS

MTLE models of immature rats were induced by lithium-pilocarpine. The rats were divided into 2 groups randomly: a control group (n=20) and an MTLE model group (n=20). At the latent stage, nissl and Timm staining were performed to evaluate the cell loss and mossy fiber sprouting. The differentially expressed proteins were separated by 2-dimensional polyacrylamide gel electrophoresis (2-DE) combined with matrix-assisted laser desorption/ ionization time of flight mass spectrometry (MALDI-TOF-MS) technology. Western blot was used to determine the differentially expression levels of partial proteins.

RESULTS

Neuron loss and abnormal mossy fiber sprouting were obviously observed in the hippocampus in the MTLE model group; 2-DE patterns of hippocampus of the MTLE model group in latent stage and the control group were established. Thirty-one differential proteins were identified by MALDI-TOF-MS, which were categorized into several groups by biological functions: synaptic and neurotransmitter release related proteins, cytoskeletal proteins, cell junctions proteins, energy metabolism and mitochondrial proteins, biological enzymes, cellular structure related proteins, signal regulating molecular and others. The expression levels of partial proteins determined by Western blot were similar to the changes of proteomics.

CONCLUSION

The differentially expressed proteins of synapse-related proteins such as dynamin-1, neurogranin and ubiquitin, which cause the synapse reorganization and mossy fiber terminal sprouting related to the formation of abnormal excitatory network, probably play critic roles in the mechanism of MTLE.