Abstract:Objective To observe the distribution and characteristics of lymphatic vessels in normal and injured mouse spinal cord, and to explore whether lymphatic vessels participate in the repair of spinal cord injury. Methods Adult male Kunming mice were randomly divided into two groups (n=36), the normal group did not damage the spinal cord, the experimental group used acupuncture to prepare a spinal cord injury model. The distribution of lymphatic endothelial cells(LECs) in the spinal cord was detected by immunohistochemistry, and the expressions of lymphatic endothelial cell markers Prospero-related homobox-1 (Prox-1), lymphatic vessel endothelial cell hyaluronic acid receptor-1 (LYVE-1), flat foot protein (podoplanin) and the vascular endothelial cell marker CD34 in the spinal cord of normal and acupuncture-injured mice were observed. The spinal cord samples were subjected to immunofluorescence staining, and the source of new LECs was explored by observing the co-expression of LYVE-1/prox-1, LYVE-1/podoplanin and CD34/Prox-1. Results Lymphangoid structures are present in the spinal cord of normal adult mice, and are distributed in segments, walking laterally between white matter and gray matter; nascent lymphangoid-like structures appear in the spinal cord at the site of acupuncture injury, and Prox-1, podoplanin, LYVE-1, and CD34 are expressed simultaneously, and the expression of Prox-1 is time-ordered; after scarring at spinal cord injury, the nascent lymphangoid-like structure disappears. Conclusion: Segmental, transversely distributed lymphangoid-like structures are present in the spinal cord of normal adult mice, and the neonatal lymphangoid-like structures are involved in the reconstruction of spinal cord injury, and the nascent lymphatic endothelial cells may originate from the surrounding existing lymphatic vessels or vascular endothelial cells.