Muscimol

The GABA_A receptor agonist muscimol is used at concentrations of 1-50 µM. Muscimol from Hello Bio used at 10 µM led to a large hyperpolarising whole-cell current in hippocampal CA1 neurons (see Fig 1 above). Action of muscimol was fully blocked by the GABA_A receptor antagonist bicuculline (100 µM).

#Protocol 1: Assay used for muscimol

• Whole cell voltage clamp recordings of CA1 pyramidal neurons from the rat hippocampal brain slice.
• Neurons were held at 0 mV and GABA_A receptor currents were evoked via applying muscimol directly to the recording chamber during continuous perfusion.
• To test muscimol’s selectivity to GABA_A receptors the experiment was repeated within the same neuron in the presence of the GABA_A receptor antagonist bicuculline (100 µM).
• Under these conditions muscimol failed to induce a hyperpolarising current.