Effects of copper on A-type potassium currents in acutely dissociated rat hippocampal CA1 neurons.
The effects of copper on voltage-gated A-type potassium currents were investigated in acutely dissociated rat hippocampal CA1 neurons using the whole-cell patch-clamp technique. Extracellular application of various concentrations of copper (1-1000 microM) reversibly reduced the amplitude of voltage-gated A-type potassium currents in a dose-dependent manner with a 50% inhibitory concentration value of 130 microM. Copper (300 microM) increased the V1/2 of the activation curve and state-inactivation curve by 17.2 and 9.0 mV, respectively. Thus, copper slowed down the activation and inactivation process of voltage-gated A-type potassium currents. This study indicated that copper reversibly inhibits the hippocampal CA1 neuronal voltage-gated A-type potassium current in a dose-dependent and voltage-dependent manner, and such actions are likely involved in the regulation of the neuronal excitability and the pathophysiology of Wilson's disease.
Niu
Zhi-Dian
ZD
Department of Neurobiology and Biophysics, School of Life Science, University of Science and Technology of China, Anhui, PR China.
Yu
Kuai
K
Gu
Yan
Y
Wang
Ming
M
She
Jia-Qi
JQ
Chen
Wei-Heng
WH
Ruan
Di-Yun
DY
D000818:Animals; D000831:Animals, Newborn; D003300:Copper / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation / Q000379:methods; D006624:Hippocampus / Q000166:cytology*; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology / Q000528:radiation effects; D009474:Neurons / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects; D018408:Patch-Clamp Techniques / Q000379:methods; D024642:Potassium Channels, Voltage-Gated / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar
D024642:Potassium Channels, Voltage-Gated; D003300:Copper