bicuculline

Bicuculline is a phthalide-isoquinoline alkaloid and a light-sensitive, competitive antagonist of Gamma-aminobutyric acid type A (GABAA) receptors. It was originally identified in 1932 from plant alkaloid extracts, including those from Dicentra cucullaria, Adlumia fungosa, and several Corydalis species. Bicuculline blocks the inhibitory action of GABA at ionotropic GABAA receptors—ligand-gated chloride channels that mediate neuronal inhibition—by binding competitively to the orthosteric site and stabilizing the receptor in a closed state. This antagonism leads to increased neuronal excitability and can induce convulsions; thus, bicuculline is widely used experimentally as a convulsant agent to model epilepsy *in vitro* (especially in hippocampal or cortical brain slices). In addition to its primary action on GABAA receptors, bicuculline also blocks small conductance calcium-activated potassium (SK) channels at higher concentrations[1][3][5][7].

Other names

(+)-bicuculline