tokens: In animals pretreated with microinjections of isoniazid , 150 micrograms , an inhibitor of activity of the GABA - synthesizing enzyme , L - glutamic acid decarboxylase , into the substantia nigra pars reticulata ( SNR ) , bilaterally , non - convulsant doses of pilocarpine , 100 and 200 mg / kg , resulted in severe motor limbic seizures and status epilepticus .