Cholinergic deafferentation enhances rat hippocampal pyramidal neuron responsiveness to locally applied nicotine

We tested whether cholinergic denervation of the hippocampas of young rats would result in an enhancement of CAI pyramidal cell responsiveness to nicotine. Electrolytic lesions of the medial septal area were performed in young male Fisher 344 rats, One month later the rats were anesthetized with pentobarbital and nicotine was locally applied to CAI pyramidal neurons using pressure microejection. The dose of nicotine required to excite the pyramidal neurons was significantly lower for cells recorded from rats with septal lesions. However, no changes in hippocampal cytisine or α-bungarotoxin binding were found.