TETRAHYDRO-9-AMINOACRIDINE PRESYNAPTICALLY INHIBITS GLUTAMATERGIC TRANSMISSION IN THE RAT AMYGDALA

The effect of the centrally active anticholinesterase inhibitor tetrah ydro-9-aminoacridine (THA) on synaptic transmission was studied in rat amygdala neurons in the in vitro slice preparation. THA reversibly su ppressed the excitatory postsynaptic potential (EPSP) in a concentrati on-dependent manner. Postsynaptic depolarization induced by alpha-amin o-5-methyl-4-isoxazole propionate (AMPA) was not decreased by THA. The se results demonstrate that THA has a presynaptic inhibitory action on the physiology of synaptic transmission in the amygdala. Pretreating the slices with atropine did not affect THA's effect, indicating that the presynaptic muscarinic receptors are not involved.