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.