Changes of metabotropic glutamate receptor subtype 1a in diffuse brain injury with secondary brain insults and the effects of 2-methyl-4-carboxyphenylglycine

摘要

Objective: To observe the changes of metabotropic glutamate receptor 1a in rat brain in a rodent model of diffuse head injury with secondary insults and the effects of 2-methyl-4-carboxyphenylglycine (MCPG).Methods: Based on Marmarous rodent model of diffuse brain injury (DBI), hypotension was made by blood withdrawal as secondary brain insults (SBI).105 male SD rats were randomized into A and B groups.The changes of mGluR1a in cerebral cortex were studied by immunohistochemistry and the effect of MCPG by HE.Each group was divided into different subgroups at different time after injury.Results: Compared with that of sham group, the number of mGluR1a positive neuron increased by 12.9±3.2 (P<0.05) 1 day after injury in the injured cerebral cortex in DBI group.However, in DBI and SBI group there was a more significant increase in the number of mGluR1a positive neuron at 4 hours after injury (15.6±3.0, P<0.05)and then the number of mGluR1a positive neuron gradually decreased.Administration of MCPG reduced total cortical necrotic neurons counts on the 7th day after injury (5.21±2.52, P<0.05).Conclusions: Brain injury can increase the gene expression of mGluR1a and the role of mGluR1a may be a key factor in the aggravation of head injury with SBI, and that MCPG may have therapeutic potential in head injury.