Fig. 3.

Postsynaptic GluN1-immunogold labeling in dendrites receiving synaptic contacts from CB1R-labeled terminals. Electron microscopic images (a–d) and bar graphs (e, f) showing size-dependent changes in the plasmalemmal and cytoplasmic GluN1-immunogold distribution in dendrites recipient to inputs from small axons or terminals that are unlabeled or contain immunoperoxidase labeling for CB1Rs in PL-PFC of adult mice receiving ∆9-THC compared with vehicle. GluN1 immunogold is seen on the plasma membrane (circles) and in the cytoplasm (small arrows) of small (a, b) and large (c, d) dendritic profiles (GluN1-De). These profiles receive symmetric synapses (block arrows) from axon terminals that are unlabeled (Un-Te) or contain dense immunoperoxidase labeling for the CB1R (CB1-Te). The GluN1-labeled dendrites are opposed to glial processes (profiles outlined with dashed line) in b–d and to a CB1R-labeled axon (CB1-Ax) in d. Curved arrows = asymmetric excitatory-type axospinous synapses in the neuropil of panel c. Scale bar = 500 nm. Bar graphs of e and f show the number of GluN1-labeled dendritic shafts in 21,170 µm² of PL-PFC tissue collected equally from ~70 microscopic images in two vibratome sections from five THC and five VEH-injected adult mice. ANOVA *p < 0.05