AUTHOR=Yuan Xiaoman , Han Siyi , Zhao Fengtian , Manyande Anne , Gao Feng , Wang Jie , Zhang Wen , Tian Xuebi 

TITLE=Rapid injection of lumbar dorsal root ganglia under direct vision: Relevant anatomy, protocol, and behaviors

JOURNAL=Frontiers in Neurology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2023.1138933

DOI=10.3389/fneur.2023.1138933

ISSN=1664-2295

ABSTRACT=Dorsal root ganglia (DRG) are anatomically well-defined structures that contain all primary sensory neurons and are distension nodules of the dorsal root in the spinal cord near the medial surface of each foramen. Therefore, DRG is considered to be a desirable target for injection to manage chronic pain. But it presents a limitation in probing deep into it without in vivo injection technology. Here, we described a technique for administering intraganglionic injections of lumbar DRG under direct vision. We use partial osteotomy rather than laminectomy, which removes more bone, to preserve spinal structures while gaining adequate DRG access. To monitor the intraoperative progress of the DRG injection, a non-toxic dye was utilized. The effectiveness of the injection on the diffusion of AAV within the ganglion was assessed by histopathology at postoperative day 21. Behavioral tests showed that neither motor nor sensory abilities were affected by saline or AAV injections. Meanwhile, the decreased pain threshold of SNI was considerably restored by pharmacological inhibition of DRG neurons. Our research achieved a more minimally invasive and intuitive intra-ganglionic injection in mice without damage to the spinal cord. In addition, the current methodology could be a valuable way that supports DRG injection preclinical investigations.