Elsevier

Neuroscience Research

Volume 26, Issue 4, December 1996, Pages 387-390
Neuroscience Research

Rapid communication
Functional expression of GABA ϱ 3 receptors in Xenopus oocytes

https://doi.org/10.1016/S0168-0102(96)01114-5Get rights and content

Abstract

Homomeric rat GABA ϱ 3 receptors were expressed in Xenopus oocytes, and their pharmacological profile was investigated electrophysiologically. GABA activated the ϱ 3 receptors with an EC50 value of 7.5 μM and a Hill coefficient of 1.6. The GABA-induced current was not antagonized by bicuculline (100 μM), but was blocked by picrotoxin (IC50: 0.68 μ M for 100 μM GABA). The current was almost insensitive to pentobarbital, diazepam and a neurosteroid, 3α-OH-DHP. Many of the pharmacological properties of the p 3 subunit were similar to those of the previously reported rat ϱ 1 and ϱ 2 subunits and GABAc receptors.

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