CGRP and MBP (myelin marker) expression in human STN. (A) Expression of CGRP in human STN. CGRP positive fibers are found in network around fiber bundles in the superficial laminae. Few fibers extend into the spinal trigeminal tract region (arrow) and the mid part of the brainstem (arrow heads). (B, C) Double-staining of CGRP (green) and MBP (red). Arrows point at MBP positive areas negative for CGRP. DAPI (blue), staining nuclei, is used in the merged pictures.