Different synaptic mechanisms of long-term potentiation induced by nicotine and tetanic stimulation in hippocampal CA1 region of rats.

AIM: To investigate whether long-term potentiation (LTP) induced by nicotine and tetanic stimulation in the hippocampal CA1 region shares different mechanisms. METHODS: Extracellular population spikes of the pyramidal cell layer in the hippocampal CA1 region were recorded in vitro. RESULTS: LTP induced by the tetanic stimulation could be facilitated by nicotine 10 micromol/L, meanwhile, the tetanic stimulation did the same effect on LTP induced by nicotine 10 micromol/L. MK-801 10 micromol/L or NG-nitro-L-arginine methyl ester (L-NAME) 20 micromol/L blocked LTP induced by tetanic stimulation, but did not inhibit LTP induced by nicotine. CONCLUSION: LTP induced by nicotine shares different synaptic mechanisms with LTP induced by tetanic stimulation.