Figure 7.

In vitro nicotine no longer restores normal function after long-term withdrawal. A, Examples of orthodromically evoked suprathreshold fEPSPs recorded in stratum radiatum (top traces) and pSpikes recorded in stratum pyramidale (bottom traces) from 3 month withdrawn animals in the presence of 500 nm nicotine (sal-slices: red; nic-slices: blue). Stimulus artifacts have been removed for clarity, and black triangles represent time of stimulus. B, Mean extracellular E-S curves from long-term withdrawn animals in the presence of 500 nm nicotine (sal-slices, n = 16; nic-slices, n = 16). Data are presented as the mean ± SEM.