Home cage activity and synaptic transmission after discontinuation of fluoxetine administration. (A) Sample data showing effects of FLX22 administration and withdrawal on nocturnal activity in two different mice. (B) CV of activity during FLX22 treatments and after discontinuation of the treatments. Data points connected by lines were from the same mice. (C) Pooled data showing reduced 1 Hz frequency facilitation at the mossy fiber synapse 4 weeks after discontinuation of fluoxetine treatments (n = 6 each, U = 0, p = 0.0022). The dotted line shows the average level of facilitation in mice treated with FLX22 for 4 to 5 weeks without discontinuation. Sample recordings are averages of 15 consecutive fEPSPs before and during 1 Hz stimulation. Scale bar: 10 ms, 0.5 mV. Data are presented as mean ± s.e.m.