Comparison of biophysical properties of α1β2 and α3β2 GABAA receptors in whole-cell patch-clamp electrophysiological recordings.

In the present study we have characterized the biophysical properties of wild-type (WT) α1β2 and α3β2 GABAA receptors and probed the molecular basis for the observed differences. The activation and desensitization behavior and the residual currents of the receptors expressed in HEK293 cells were determined in whole-cell patch clamp recordings. Kinetic parameters of α1β2 and α3β2 activation differed significantly, with α1β2 and α3β2 exhibiting rise times (10-90%) of 24 ± 2 ms and 51 ± 7 ms, respectively.

Delineation of the functional properties and the mechanism of action of AA29504, an allosteric agonist and positive allosteric modulator of GABA receptors.

The retigabine analog 2-amino-4-[(2,4,6-trimethylbenzylamino)-phenyl]-carbamic acid ethyl ester (AA29504) is a positive allosteric modulator (PAM) of γ-aminobutyric acid receptors (GABARs), and the modulator has been used in ex vivo/in vivo studies to probe the physiological roles of native δ-containing GABARs. In this study, the functional properties and mode of action of AA29504 were investigated at human GABARs expressed in Xenopus oocytes by two-electrode voltage clamp electrophysiology. AA29504 was found to be an allosteric GABAR agonist displaying low intrinsic activities at 3-30 μM.

Functional properties and mechanism of action of PPTQ, an allosteric agonist and low nanomolar positive allosteric modulator at GABA receptors.

The former sedative-hypnotic and recreational drug methaqualone (Quaalude) is a moderately potent, non-selective positive allosteric modulator (PAM) at GABA receptors (GABARs) (Hammer et al., 2015). In the present study, we have identified a novel methaqualone analog, 2-phenyl-3-(p-tolyl)quinazolin-4(3H)-one (PPTQ), in a screening of 67 analogs at five αβγ GABAR subtypes and delineated its functional properties and mechanism of action at wild-type and mutant GABARs expressed in Xenopus laevis oocytes by two-electrode voltage clamp electrophysiology.

Molecular Cloning and Functional Expression of the Equine K+ Channel KV11.1 (Ether à Go-Go-Related/KCNH2 Gene) and the Regulatory Subunit KCNE2 from Equine Myocardium.

The KCNH2 and KCNE2 genes encode the cardiac voltage-gated K+ channel KV11.1 and its auxiliary β subunit KCNE2. KV11.