Modulation of firing activity by endogenous GABAA receptors in the globus pallidus of MPTP-treated parkinsonian mice

• Published in: Neuroscience bulletin Vol. 29; no. 6; pp. 701 - 707
• Main Authors: Chen, Xin-Yi, Xue, Yan, Wang, Hua, Zhu, Su-Hong, Hao, Xiao-Meng, Chen, Lei
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.12.2013
• Subjects: Action Potentials - physiology; Anatomy; Anesthesiology; Animals; Biomedical and Life Sciences; Biomedicine; GABA Antagonists - pharmacology; Globus Pallidus - drug effects; Globus Pallidus - physiopathology; Human Physiology; Male; Mice; Mice, Inbred C57BL; MPTP Poisoning - physiopathology; Neurology; Neurons - drug effects; Neurons - physiology; Neurosciences; Original; Original Article; Pain Medicine; Pyridazines - pharmacology; Receptors, GABA-A - physiology; GABA; receptor; single unit recording; globus pallidus; Parkinson’s disease
• ISSN: 1673-7067; 1995-8218
• DOI: 10.1007/s12264-013-1351-x

The globus pallidus in rodents, equivalent to the external segment of the globus pallidus in primates, plays an important role in movement regulation. Previous studies have shown abundant γ-aminobutyric acid (GABA)ergic innervation and GABA A receptors in the globus pallidus. In this study, we investigated the effects of endogenous GABA A receptors on the spontaneous firing activity of pallidal neurons in both normal and MPTP-treated mice using multi-barrel electrodes extracellular recordings in vivo . We found that in normal mice, pressure ejection of 0.1 mmol/L gabazine, a specific GABA A receptor antagonist, increased the spontaneous firing rate of globus pallidus neurons by 27.6 ± 5.6%. Furthermore, in MPTP mice (14 days after MPTP treatment), 0.1 mmol/L gabazine increased the firing rates by 51.0 ± 7.9%, significantly greater than in normal mice. These results suggest that endogenous GABA A receptors modulate the activity of globus pallidus neurons. The present findings may provide a rationale for investigations into the potential role of GABA A receptors in Parkinson’s disease.