Male and Female Mice Differ for Baseline and Nicotine-Induced Event Related Potentials

The usage patterns and biological effects of cigarette smoking differ significantly among men and women. This study seeks to clarify the interaction that exists between nicotine and biological gender by investigating changes in brain electrical activity after acute nicotine treatment. The P20, N40, and P80 components of the auditory evoked potential were examined in male and female C57BL/6J mice using a paired-stimulus gating paradigm. Consistent with previously published data, acute nicotine resulted in increased gating of the P20 but a decrease in that of N40. Nicotine also resulted in a lengthening of P20 latency but a decrease in that of N40 and P80. The P80 latencies of male and female subjects were differentially affected by nicotine, as males appeared to be more sensitive to its shortening effect. Males and females also exhibited differences in N40 and P80 amplitudes, both of which were smaller in males. The effects of gender on auditory evoked potential amplitude suggest dimorphic signaling in the N40 and P80 generators. Whether this electrophysiological sexual dimorphism has functional consequences for sensory or cognitive abilities requires additional research.