Nicotine self‐administration is associated with decreased expression of the glial glutamate transporter (GLT‐1) and the cystine‐glutamate exchange protein xCT within the nucleus accumbens core (NAcore). N‐acetylcysteine (NAC) has been shown to restore these proteins in a rodent model of drug addiction and relapse. However, the specific molecular mechanisms driving its inhibitory effects on cue‐induced nicotine reinstatement are unknown. Here, we confirm that extinction of nicotine‐seeking behavior is associated with impaired NAcore GLT‐1 function and expression and demonstrates that reinstatement of nicotine seeking rapidly enhances membrane fraction GLT‐1 expression. Extinction and cue‐induced reinstatement of nicotine seeking was also associated with increased tumor necrosis factor alpha (TNFα) and decreased glial fibrillary acidic protein (GFAP) expression in the NAcore. NAC treatment (100 mg/kg/day, i.p., for 5 d) inhibited cue‐induced nicotine seeking and suppressed AMPA to NMDA current ratios, suggesting that NAC reduces NAcore postsynaptic excitability. In separate experiments, rats received NAC and an antisense vivo‐morpholino to selectively suppress GLT‐1 expression in the NAcore during extinction and were subsequently tested for cue‐induced reinstatement of nicotine seeking. NAC treatment rescued NAcore GLT‐1 expression and attenuated cue‐induced nicotine seeking, which was blocked by GLT‐1 antisense. NAC also reduced TNFα expression in the NAcore. Viral manipulation of the NF‐κB pathway, which is downstream of TNFα, revealed that cue‐induced nicotine seeking is regulated by NF‐κB pathway signaling in the NAcore independent of GLT‐1 expression. Ultimately, these results are the first to show that immunomodulatory mechanisms may regulate known nicotine‐induced alterations in glutamatergic plasticity that mediate cue‐induced nicotine‐seeking behavior.

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The development of compartmentalized neuron culture systems has been invaluable in the study of neuroinvasive viruses, including the alpha herpesviruses Herpes Simplex Virus 1 (HSV-1) and Pseudorabies Virus (PRV). This chapter provides updated protocols for assembling and culturing rodent embryonic superior cervical ganglion (SCG) and dorsal root ganglion (DRG) neurons in Campenot trichamber cultures. In addition, we provide several illustrative examples of the types of experiments that are enabled by Campenot cultures: 1. Using fluorescence microscopy to investigate axonal outgrowth/extension through the chambers, and alpha herpesvirus infection, intracellular trafficking, and cell-cell spread via axons. 2. Using correlative fluorescence microscopy and cryo electron tomography to investigate the ultrastructure of virus particles trafficking in axons.