Fig. 3

Thoracic to cervical DRG extraction. a Affix the spinal column segment containing thoracic and cervical levels to the Sylgard plate using three insect pins placed through vertebral discs—one each in the approximate regions of T10-T11, T2-T3, and cervical level 3–4 (C3–C4). R, rostral; C, caudal, D, dorsal; V, ventral (maintained in all panels). b–d Remove the first membrane lining the spinal canal by clasping it in the lower thoracic region and pulling up towards the cervical level (right to left, here). Take care that cervical DRG are not removed with the membrane. e, f Extract a second layer in a similar fashion. DRG in the cervical region nearly always come away with this membrane, which can be useful for extracting DRG as they are individually pulled from their foramina. See Additional file 4 for how this is done. g, h For thoracic ganglia that remain within foramina, which is most, if not all, pick up individual ganglia from their distally projecting axon bundle as done at the lumbar level (T9 DRG removed, here). All depicted steps are shown in Additional file 4. Scale bars = 5 (a–d) and 1 (e–h) mm