Triton X-100 inhibits L-type voltage-operated calcium channels.

Triton X-100 (TX-100) is a nonionic detergent frequently used at millimolar concentrations to disrupt cell membranes and solubilize proteins. At low micromolar concentrations, TX-100 has been reported to inhibit the function of potassium channels. Here, we have used electrophysiological and functional techniques to examine the effects of TX-100 on another class of ion channels, L-type voltage-operated calcium channels (VOCCs).

On the disruption of biochemical and biological assays by chemicals leaching from disposable laboratory plasticware.

Plastic consumables, used universally in bioscience laboratories, are presumed inert with respect to bioassay outcomes. However, it is clear that many pipette tips, microfuge tubes, and other plastic disposables leach bioactive compounds into assay solutions, profoundly affecting data and experimental interpretation. In this paper we discuss the nature and sources of leachates and review several examples of compromised bioassay data that speak to the probable widespread nature of this largely unrecognised source of error.

The Cys-loop pentameric ligand-gated ion channel receptors: 50 years on.

This year, 2011, the Department of Pharmacology at the University of Alberta celebrated its 50th anniversary. This timeframe covers nearly the entire history of Cys-loop pentameric ligand-gated ion channel (pLGIC) research. In this review we consider how major technological advancements affected our current understanding of pLGICs, and highlight the contributions made by members of our department.

Benzodiazepine modulation of the rat GABAA receptor α4β3γ2L subtype expressed in Xenopus oocytes.

The effects of benzodiazepines on GABA(A) receptors are dependent largely on the particular α subunit isoform that is present in the receptor pentamer. The inclusion of either the α4 or α6 subunit is generally thought to render the receptor insensitive to classical benzodiazepines. We expressed the rat α4β3γ2L subtype in Xenopus oocytes and observed that both diazepam and flunitrazepam significantly potentiated GABA-gated currents.

Isomerization of the proline in the M2-M3 linker is not required for activation of the human 5-HT3A receptor.

Each subunit of the cation-selective members of the Cys-loop family of ligand-gated ion channels contains a conserved proline residue in the extracellular loop between the second and third transmembrane domains. In the mouse homomeric 5-hydroxytryptamine type 3A (5-HT(3)A) receptor, the effects of substitution of this proline by unnatural amino acids led to the suggestion that trans-cis isomerization of the protein backbone at this position is integral to agonist-induced channel opening [Nature (2005) vol. 438, pp.

A single point mutation of the GABA(A) receptor alpha5-subunit confers fluoxetine sensitivity.

Fluoxetine has been reported to be a novel allosteric modulator of GABA(A) receptors with the notable exception of receptors that contain the alpha5-subunit isoform [Robinson, R.T., Drafts, B.