Figure 2.
Adenosine A2A receptor immunoreactivity in the thoracic spinal cord. A, Low magnification of A2AR immunoreactivity visualized with DAB. Labeling was observed throughout the spinal cord. Even at low magnification, a compact region of dense staining is clearly seen in the IML. Staining is also evident in the dorsal horn (DH) and ventral horn (VH). B, Low magnification of the IML. A compact region of punctate staining was observed in the IML adjacent to the white matter (WM), distinguishing this area from the surrounding neuropil. C, High magnification of the boxed area in B. At higher magnification, the punctate structures are clearly identifiable. D, In the dorsal horn, staining of fibers was dense in the superficial lamina, and labeled neuronal somata were also observed in lamina II (arrows). I, Lamina I; II, lamina II. E, In the ventral horn-labeled fibers, somata and proximal dendrites of large neurons were observed. F, In the vicinity of the central canal, labeling was observed in somata (arrow) as well as in presumptive fibers. G, High magnification of A2AR immunuoreactivity in the IML visualized with Cy3. A dense region of punctate staining can be observed in the IML. H, Sympathetic preganglionic neurons retrogradely labeled with Fluorogold in the same section as in G, viewed under UV illumination.