In addition to Bdnf and Ntrk2, we examined NAc transcript levels of several other synaptic targets known to be important for behavioral response to cocaine. Levels of the transcript for the Drd1 dopamine receptor did not show a significant main effect of antibiotic or cocaine, but there was a significant cocaine x antibiotic treatment interaction (F(1,40) = 7.74, p = 0.008), and post-hoc testing demonstrated a significant difference between the two cocaine-treated groups (Fig. 7a - p = 0.04). There were no significant alterations in levels of Drd2 transcript (Fig. 7b). Additionally, levels of the Gria2 transcript, which encodes the GluR2 AMPA receptor, showed a main effect of cocaine (F(1,42) = 11.96; p = 0.001) and a cocaine x antibiotic interaction F(1,42) = 4.43; p = 0.04) with post-hoc testing demonstrating significant difference between the antibiotics + cocaine treatment group and both saline treated groups (Fig. 7c). There were no significant differences in levels of Dlg4 (which encodes postsynaptic density protein 95 or PSD-95) or the NMDA receptor transcripts Grin2a and Grin2b (Fig. 7d–f).
