Effect of High-Frequency Stimulation in the Pedunculopontine Nucleus on Neuronal Activity and Neurotransmitters in the Globus Pallidus Internus of Rats / 天津医药

ABSTRACT

Objective To study the effect of high frequency stimulation (HFS) in pedunculopontine nucleus (PPN) on the neuronal activities of globus pallidus internus (Gpi) in Parkinson’s disease (PD) model rats, and the mechanisms there-of. Methods Seventy male Sprague-Dawley rats were divided into two groups, control group (n=30) and PD model group (n=40). PD rat model was established by the injection of 6-OHDA into substantia nigra pars compacta (SNc) on the right side of the brain with stereotactic technique. Electrophysiological recordings were made in anaesthetized rats to investigate the ef-fects of HFS-PPN on the firing rate of the GPi neurons. Brain microdialysis combined with high-performance liquid chroma-tography was applied to detect glutamate (Glu) andγ-aminobutyric acid (GABA) levels in GPi. Results HFS-PPN caused an excitatory reaction of the majority of neurons recorded in the GPi in PD model group and control group. The mean firing rate of GPi excited neurons was significantly increased (P﹤0.01). The levels of Glu were reduced under HFS-PPN and the levels of GABA were not affected (P>0.05).Conclusion HFS-PPN heightened the electrical activity of GPi neurons and re-duced the level of Glu. These excitatory effects were probably realized by PPN-GPi direct path or other indirect path.