Related Experiment Video
Updated: Jun 17, 2026
Profiling Voltage-gated Potassium Channel mRNA Expression in Nigral Neurons using Single-cell RT-PCR Techniques
Published on: September 27, 2011
Functional expression of a large-conductance Ca2+-activated K+ channel in mouse substantia nigra pars compacta
Wenting Su1, Xueqin Song, Juan Juan Ji
1State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China.
Abstract:
The existence of large-conductance Ca(2+)-activated K(+) (BK) channels in substantia nigra pars compacta (SNc) has been a matter of debate. Using the patch-clamp technique in the inside-out configuration, we have recorded BK channel currents in SNc dopaminergic neurons. The channel has a conductance of 301 pS with a slight inward rectification and is both voltage- and calcium-dependent. Paxilline, a specific BK channel blocker, can completely block the channel, while tetraethylammonium (TEA), a nonspecific blocker of voltage-gated potassium channels, reduces its conductance and a high concentration of TEA (30 mM) inhibits its activity. ATP and GTP reduce the channel activity, while ADP is less potent, and AMP has no effect. The channel is also sensitive to changes in intracellular pH. Our results indicate that functional BK channels are expressed in SNc and suggest the possibility that the BK channel may be involved in the response of SNc dopaminergic neurons to metabolic stress.
