The Effect of Bicuculline, Metrazol, Picrotoxin and Strychnine on the Release of [³h]gaba From Rat Brain Slices

Each of the four convulsants used significantly influenced the release of [ 3 H]‐GABA from brain slices, without affecting [ 3 H]GABA uptake. Bicuculline (10 −5 M, but not 10‐fold higher or lower concentrations) potentiated the electrically evoked release of [ 3 H]GABA but not the resting release, whereas metrazol (10 −4 to 10 −6 M) was found to inhibit resting but not electrically evoked release. Strychnine (10 −4 and 10 −5 M) and picro‐toxin (10 −4 M) inhibited electrically evoked release.