Fig. 5.

Catecholamine depletion decreases LTP. Forskolin application restores LTP to control level. Calculations and markings are as in Figure 2. Note that Depletion andDepletion + Forskolin experiments were performed on the same slice (n = 5), whereas Controlwas taken from nondepleted rats of the same age and carried out under the same conditions (n = 5). All experiments were performed within a 1.5 week period without interruption by other experiments. We did not note any differences in slice condition, fEPSP threshold or amplitude, or population spike threshold between control and depleted slices.