Fig. 2.

β1-AR expression in high-likelihood inhibitory dendrites of layer III dlPFC

(A-G) Electron microscopy photomicrographs depicting β1-AR expression in high-likelihood inhibitory dendrites (pseudocolored pink) of young macaque layer III dlPFC (8-10y). Dendrites were classified as high-likelihood inhibitory based on multiple criteria, including multiple asymmetric synapses (presumed excitatory, black arrows) on the dendritic shaft, and no apparent spines in plane or in nearby sections. β1-AR immunogold [or immunoperoxidase nickel DAB (C)] labeling (arrowheads) indicate the presence of β1-AR expression in the cytoplasm (grey arrowheads), in extrasynaptic segments of the membrane (orange arrowheads), or in or near the post-synaptic density (red arrowheads). Label that appeared very close to a membrane but not clearly adhered was color coded with hatching to capture that they may be undergoing trafficking to a specific membrane compartment. Red/grey hatching captures possible trafficking to the synapse, and orange/grey hatching captures possible trafficking to an extrasynaptic location. ax, axon (pseudocolored blue); mt, mitochondria. Scale bars, 200 nm. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)