(A) Digitally colored image of SAN tiled from 4 TEM images. (B) Zoomed-in picture of the area outlined by the rectangle in A. A and B illustrate close anatomical interactions between telocytes (blue), PMC (red), nerves from the neuronal plexus (green), and endocardial cells (yellow). Erythrocytes in the TEM images are indicated by the letters Er. It is worth noting that the telopodes and podomers from the telocyte are projected to the capillary, to the PMC, and to the neuronal fiber. They approach the membrane of the pacemaker and endocardial cell as close as several hundreds of nanometers, without making direct contact with the membrane of these cells. Pink color highlights the exosomal vesicles shed from the telocyte. Abbreviations as in Figure 11.