The opening effect of pregabalin on ATP-sensitive potassium channels in differentiated hippocampal neuron-derived H19-7 cells.
OBJECTIVE
Adenosine triphosphate (ATP)-sensitive K+ (KATP) channels can couple an intracellular metabolic state to an electrical activity, which is important in the control of neuronal excitability and seizure propagation. We investigated whether the newer antiepileptic drug, pregabalin (PGB), could exert effects on KATP channels in differentiated hippocampal neuron-derived H19-7 cells.


METHODS
The inside-out configuration of the patch-clamp technique was used to investigate KATP channel activities in H19-7 cells in the presence of PGB. Effects of various compounds known to alter KATP channel activities were compared.


RESULTS
The activity of KATP channels in these cells was characterized. The single-channel conductance from a linear current-voltage relation was 78 +/- 2 pS (n = 8) with a reversal potential of 63 +/- 2 mV (n = 8), similar to that of KATP channels reported in pancreatic beta cells. 2,4-Dinitrophenol activated channel activity, but the further addition of glucose (20 mM) or glibenclamide (30 microM) could offset these increments. PGB significantly opened these KATP channel activities in a concentration-dependent fashion with a median effective concentration (EC50) value of 18 microM. A significant increase was noted in the mean open lifetime of KATP channels in the presence of PGB (1.71 +/- 0.04 to 5.62 +/- 0.04 ms).


CONCLUSIONS
This study suggests that in differentiated hippocampal neuron-derived H19-7 cells, the opening effect on KATP channels could be one of the underlying mechanisms of PGB in the reduction of neuronal excitability.
Huang
Chin-Wei
CW
Department of Neurology, National Cheng-Kung University Medical Center, Tainan, Taiwan.
Huang
Chao-Ching
CC
Wu
Sheng-Nan
SN
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology*; D002454:Cell Differentiation; D002460:Cell Line; D004140:Dinitrophenols / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005947:Glucose / Q000494:pharmacology; D005905:Glyburide / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects*; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D018408:Patch-Clamp Techniques; D015221:Potassium Channels / Q000187:drug effects* / Q000502:physiology; D000069583:Pregabalin; D051381:Rats; D017207:Rats, Sprague-Dawley; D005680:gamma-Aminobutyric Acid / Q000031:analogs & derivatives* / Q000494:pharmacology
D000927:Anticonvulsants; D004140:Dinitrophenols; D015221:Potassium Channels; D000069583:Pregabalin; D005680:gamma-Aminobutyric Acid; D000255:Adenosine Triphosphate; D005947:Glucose; D005905:Glyburide