[Effects of electrical stimulation of sciatic nerve on synaptic plasticity of spinal dorsal horn, hippocampal CA1 region and spinal c-fos, hippocampal CA1 region expression in neonatal rats].

OBJECTIVE:To explore the response to nociceptive stimuli in spinal cord of neonatal rat and observe the electrical stimulation of sciatic nerve on synaptic plasticity of spinal dorsal horn, hippocampal CA1 region and spinal c-fos, hippocampal CA1 region expression in neonatal rats. METHODS:The rats were divided into neonatal and adult groups. The evoked potentials of left spinal dorsal horn from T13-L1 and right hippocampal CA1 region were recorded. After conditional electric stimulations, the potential amplitudes were recorded. When the incubation period reached 120 min, D-AP5 was added to spinal cord of rats and resulting changes in field potential and c-fos expression were recorded. RESULTS:Long-term potentiation (LTP) in neonatal rats was mainly evoked by A-type nerve fibers whereas LTP in adult rats was mainly evoked by C-type nerve fibers. C-fos expression was significantly increased in superficial, deep layers of spinal dorsal horn, ventral horn and hippocampal CA1 region in neonatal rats. CONCLUSION:Pain signals change with age.