Referenced in: none

Automatically associated channels: SK1 , SK2 , SK3

Title: The antidepressant fluoxetine blocks the human small conductance calcium-activated potassium channels SK1, SK2 and SK3.

Authors: Georg C Terstappen, Annalisa Pellacani, Laura Aldegheri, Francesca Graziani, Corrado Carignani, Giordano Pula, Caterina Virginio

Journal, date & volume: Neurosci. Lett., 2003 Jul 31 , 346, 85-8

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/12850554

Abstract
The effects of fluoxetine (Prozac) on the activity of human small-conductance calcium-activated potassium (SK) channels were investigated utilizing a functional fluorescence assay with bis-(1,3-dibutylbarbituric acid)trimethine oxonol (DiBAC(4)(3)). Fluoxetine blocked SK channels stably expressed in HEK 293 cells in a concentration-dependent manner displaying half-maximal inhibitory concentrations (IC(50)) of 9 microM for hSK1, 7 microM for hSK2 and 20 microM for hSK3. The block of hSK3 channels was confirmed by whole cell patch-clamp recordings of the recombinant cells and human TE 671 cells. Fluoxetine also inhibited [(125)I]apamin binding in a concentration-dependent manner displaying IC(50) values of 63 microM for hSK1, 148 microM for hSK2 and 295 microM for hSK3. These results provide new information concerning the mechanism of therapeutic and/or side effects of one of the most widely used antidepressant drugs.