Resting and electrical stimulation evoked[3H]5-HT and [3H]NA efflux in the hippocampus of P2rx7+/+ and P2rx7−/− mice, respectively.

Tissue slices were loaded with [3H]5-HT or [3H]NA and then superfused with Krebs’ solution. After 60 min preperfusion, slices were stimulated electrically with the following parameters: 25 V, 1 msec, 2 Hz, 240 shocks. The release of radioactivity was expressed in Bq/g. For the calculation of the resting [3H]5-HT/[3H]NA efflux, the tritium content of the sample collected immediately before the first electrical stimulation period was taken into account. Electrical stimulation-induced [3H]5-HT/[3H]NA efflux (S1) was expressed by calculating the net release in response to electrical stimulation by the area-under-the-curve method. The number of experiments are in parentheses. *P