The 5-HT2 agonist αme5HT (10 μm) reduced the sAHP and eliminated gain increases caused by noise in layer 2/3 pyramidal neurons. A, AHPs after 30 spikes at 50 Hz in control solution and during application of αme5HT. The slow component of the AHP was greatly reduced. B, Typical f–I relationships in control solution. The curve obtained with noise diverged from the no-noise curve, showing a gain increase. The solid line is a fit to the f–I relationship with noise, as described in Figure 2. C, f–I relationship of the same cell in αme5HT, showing a nearly constant rate difference between curves obtained with and without noise. D, Bar graph showing the mean additive effect of noise in control solution and while applying αme5HT. E, Mean gain change by noise in control solution and in αme5HT.
