Skip to main content
. Author manuscript; available in PMC: 2021 Apr 1.
Published in final edited form as: Biol Psychiatry. 2019 Aug 6;87(7):619–631. doi: 10.1016/j.biopsych.2019.07.024

Figure 6. Chronic Δ9-THC differentially alters mGluRI-induced synaptic plasticity distinct NAcs glutamate afferents.

Figure 6.

A-D. Effects of a 10 min application of the mGluRI agonist, DHPG, on oEPSCs evoked via ChR2-activation of glutamate afferents to the NAcs. Shown for each brain region is a mean time-course of the oEPSCs, normalized to 100 % of control, for the chronic Δ9-THC and vehicle groups (below) and representative averaged waveforms from individual cells from each group (above). In each instance, control mean oEPSCs collected before DHPG application are indicated by black dashed lines, whereas oEPSCs averaged from individual sweeps, collected from minute 35 to minute 42, are indicated by solid lines in neurons from vehicle- (gray) or Δ9-THC-treated (green) animals. A. Effects of DHPG on mPFC afferents to NAcs (* = p < 0.001, repeated measures ANOVA, F20,260 = 2.7, time vs. treatment interaction). B. Effects of DHPG on oEPSCs evoked by ChR2-activation of vHipp glutamate afferents to the NAcs (** = p < 0.0001, repeated measures ANOVA, F20,260 = 13.2, time vs. treatment interaction). C. Effects of DHPG on oEPSCs evoked by ChR2-activation of BLA glutamate afferents to the NAcs shows that DHPG-LTD was significant compared to baseline in all groups (one-way ANOVA, F3,20 = 5.1, p = 0.009; # = p < 0.05, Newman-Keuls post-hoc test), but there was no difference in LTD among groups. D. Effects of DHPG on oEPSCs evoked by ChR2-activation of VTA THCre neuron glutamate afferents to the NAcs (time vs. treatment interaction not significant, repeated measures ANOVA, F20,260 = 1.4,). E. Summary of DHPG effect on normalized oEPSCs, evoked by ChR2-activation of afferents arising from mPFC (a), vHipp (b), BLA (c), and the VTA (d) for the chronic vehicle (Veh), chronic Δ9-THC, and chronic Δ9-THC + AM251 (THC+AM) groups. * = p < 0.05, ** = p < 0.0001, 1-way ANOVA with Holm-Sidak post-hoc comparison. # = p < 0.05, 1-way ANOVA with Newman-Keuls post-hoc. Number of neurons/Rat per group: A. Veh: 7/6, THC: 8/5. B. Veh: 8/5, THC: 7/5. C. Veh: 5/5, THC: 6/5. D. Veh: 7/6, THC: 9/6. Ea. Veh: 7/6, THC: 8/5, THC+AM: 8/5. Eb. Veh: 8/5, THC: 7/5, THC+AM: 5/4. Ec. Veh: 6/5, THC: 5/5, THC+AM: 6/5. Ed. Veh: 7/6, THC: 8/6, THC+AM: 7/5.