Fig. 5.

Effects of isoproterenol on conditioned responses in the dorsal and the ventral hippocampus. Data are shown for the 2nd response (A & B) and the steady-state response (C & D) in a train. In drug condition, only data with adjusted PS are shown. Example traces are given in inserts (stimulation artifacts are truncated for clarity). In plots A and B only the first two responses induced in a 20 Hz train are shown to illustrate changes in paired-pulse facilitation. In plots C and D only the first and tenth (i.e. last) responses are shown to illustrate the change induced in steady-state responses by 5 Hz and 40 Hz stimulation. Calibration bars: 0.5 mV and 10 ms in A and B, 1 mV and 10 ms in C and D. All stimulation artifacts are truncated for clarity. Asterisks indicate statistically significant drug-induced differences at p < 0.05 (independent t-test). Note that isoproterenol significantly enhances paired-pulse and steady-state facilitation of PS in the dorsal hippocampus only.