The influence of cholinergic drugs on evoked field potentials in the gyrus dentatus of immobilized rats.

We reported previously the elicitation of presumably monosynaptic evoked field potentials in the dentate gyrus of immobilized rats by stimulation of the medial septal nuclei. The septo-hippocampal pathway mediating this evoked potential (SHEP) is widely assumed to be cholinergic in nature. In order to further verify this assumption we studied the effects of muscarinic drugs on the SHEPs. Scopolamine as muscarinic cholinolytic and arecoline as muscarinic cholinergic agent influenced the SHEP in the expected manner. We conclude that the SHEP is elicited by cholinergic muscarinic activation.