Inhibition of tacrine on delayed rectifier and transient outward potassium currents in cultured rat hippocampal neurons.
- Author:
Wei ZHANG
1
;
Hong-wei JIN
;
Shao-feng XU
;
Lin-tao QU
;
Xiao-liang WANG
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Animals, Newborn; Cells, Cultured; Cholinesterase Inhibitors; pharmacology; Female; Hippocampus; cytology; physiology; Male; Neurons; cytology; physiology; Patch-Clamp Techniques; Potassium Channels; drug effects; Potassium Channels, Inwardly Rectifying; drug effects; Rats; Rats, Wistar; Tacrine; pharmacology
- From: Acta Pharmaceutica Sinica 2004;39(2):93-96
- CountryChina
- Language:Chinese
-
Abstract:
AIMTo study the effects of tacrine on IK and IA potassium current in primary cultured rat hippocampal neurons.
METHODSWhole cell patch clamp and primary rat hippocampal neuron cultures were used.
RESULTSTacrine was shown to reduce the amplitude of IK and IA, in concentration-dependent manners. The IC50s at +40 mV for reduction of IK and IA were 23 and 52.6 mumol.L-1, respectively. Tacrine (30 mumol.L-1) shifted the steady state activation of IK and IA to negative potentials by 12 and 15 mV, respectively. The V1/2 of activation curves for IK current before and after the application of tacrine were (6.7 +/- 1.4) mV and (-5.4 +/- 1.3) mV, respectively. The k of activation curves for IK current was 13.4 + 1.3 and 12.5 + 1.4 without and with tacrine, respectively. The V1/2 of activation curve for IA current were (-9.9 +/- 2.6) mV and (-24 +/- 5) mV in the absence and presence of tacrine, respectively, and the k value was not changed.
CONCLUSIONTacrine inhibited IK and IA currents in rat hippocampal neurons and it is more potent for blocking IK.
