In order to harvest the dorsal root ganglion, first perform intracardiac perfusion with PBS containing heparin followed by 4% PFA or 10% neutral buffered formalin. Once this is complete, you will decapitate, use a scalpel to cut rostral-caudal though the skin and fascia. Remove the overlying musculature. Then starting rostral, use a bone nipper or rongeur to cut the spinal column at 10 and 2 o'clock and remove each lamina one by one in this fashion. Once you have performed laminectomy through the lumbar region, you will slowly cut the dorsal and ventral spinal roots, beginning at the cervical region and moving down one level at a time till you free the spinal cord. Be careful to cut these roots as close to the spinal cord as possible or you may remove the DRG by mistake. Once the cord is removed, you should be able to visualize the dorsal root ganglion. USe the images in the linked publication to determine the exact lumbar DRG you want to isolate. At this point, you want to slowly break away the bone that encircles the DRG so that is can be freed. There is a lot of connective tissue so be sure that you have cut throughthis as well. Then you can carefully grab the DRG by one of the protruding nerve roots, careful not to grab the actual ganglion or you can crush the tissue of interest. You can either count down to the level from the floating rib or up via the sciatic nerve. The images should be very helpful.
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