STUDY ON EXCITABILITY CHANGE OF HIPPOCAMPAL CA1 NEURONS AFTER FLUID PERCUSSION INJURY
液压打击损伤后海马CA1区神经元兴奋性变化的研究

The effects of traumatic head injury on the neuronal activity in the hippocampal CA1 area and the effects of emodin on the neuronal hyperexcitability and synaptic transmission were studied. The fluid percussion brain injury rat model and extracellular recording method were used. The field excitatory postsynaptic potential and population spike evoked by stimulating Schaffer collaterals were collected from the ipsilateral (impact side) and the contralateral rat hippocampus CA1 areas in vitro. And the field potentials, including the field excitatory postsynaptic potential and the population spike were analyzed. Results showed that the slope of the field excitatory postsynaptic potential in the ipsilateral area was obviously greater than that in the contralateral area. And the number of the population spike was increased significantly while the latency of the population spike was decreased obviously. Furthermore, the evoked field potentials in hippocampus CA1 areas were decreased significantly by emodin even after the brain injury. Studies indicated that traumatic head injury may lead to hyperexcitability of hippocampal CA1 pyramidal neurons. Emodin can depress the neuronal hyperexcitability, which suggests that emodin plays an important role in protecting the central nervous system from neuronal damage after traumatic head injury.