Expression and significance of GIT1 in hippocampus of lithium-pilocarpine-induced epileptic rats

Abstract

Objective  To investigate the expression changes of G-protein-coupled receptor kinase-interacting protein 1 (GIT1) in lithium-pilocarpine-induced epileptic rat model and explore its role in the genesis and development of epilepsy.  Methods  The lithium-pilocarpine-induced model of status epilepticus (SE) was established in 42 specific pathogen free (SPF) male adult Wistar rats, and those rats were randomly divided into control group and 6 epilepsy groups (1, 3, 7, 14, 30, 60 d after SE). The expression of GIT1 mRNA was detected by fluroescent quantitative polymerase chain reaction (PCR), while the expression of GIT1 protein was examined by Western blotting and immunohistochemistry was applied to test the expression of CA1 region, dentate gyrus and parahippocampal cortex in rat hippocampus at different time points.  Results  GIT1 mRNA level rised in acute phase on 1st and 3rd day after SE (P = 0.012, 0.002), then increased continously in latency on 7th and 14th day (P = 0.003, 0.001), and reached the peak in chronic phase on 30th and 60th day (P = 0.000, for all). GIT1 protein expression rised in acute phase and increased continously in chronic phase, but there was no significant difference compared with control group (P > 0.05, for all). Then, it reached the peak in chronic phase (P = 0.000, for all). Until the 30th day, the GIT1 expression of CA1 region, dentate gyrus and parahippocampal cortex in the hippocampus of rats in 6 epilepsy groups was significantly higher than that of control group (P = 0.000, for all).  Conclusions  The up-regulated expression of GIT1 in the hippocampus of epileptic rat was probably involved in the formation process of chronic epilepsy by regulating cytoskeleton dynamic regrouping to influence excitatory neural networks.

DOI: 10.3969/j.issn.1672-6731.2015.06.011