Figure 8.
Presynaptic CRF2 and D1/5 receptors interact to increase putative BLA–mPFC EPSCs in chronic cocaine-treated rats. A, Bar graph summarizes the effects of r/hCRF (100 nm), SKF (10 μm), and a combination (50 nm r/hCRF plus 1 μm SKF) on EPSCs recorded from mPFC–layer V pyramidal neurons loaded with GDPβS (1 mm) from chronic cocaine-treated rats. Data from neurons without GDPβS are included for comparison. Vertical solid lines divide the data for each drug-treatment group. GDPβS (1 mm) did not block the effects of the individual ligands or their combination. B, Representative traces of EPSCs evoked by pairs of stimuli at different interstimulus intervals at baseline (left column) and after r/hCRF (100 nm; right column, top traces), SKF (10 μm; right column, middle traces), and the combination (50 nm r/hCRF plus 1 μm SKF). Right, Paired-pulse ratios (PPR = EPSC2/EPSC1) plotted as a function of interstimulus interval for each treatment group. PPR values were decreased significantly by r/hCRF (100 nm) compared with baseline only at the shortest interval (50 ms).