title: Expression changes of nerve cell adhesion molecules L1 and semaphorin 3A after peripheral nerve injury.
abstract: The expression of nerve cell adhesion molecule L1 in the neuronal growth cone of the central nervous system is strongly associated with the direction of growth of the axon, but its role in the regeneration of the peripheral nerve is still unknown. This study explored the problem in a femoral nerve section model in rats. L1 and semaphorin 3A mRNA and protein expressions were measured over the 4-week recovery period. Quantitative polymerase chain reaction showed that nerve cell adhesion molecule L1 expression was higher in the sensory nerves than in motor nerves at 2 weeks after injury, butvice versafor the expression of semaphorin 3A. Western blot assay results demonstrated that nerve cell adhesion molecule L1 expression was higher in motor nerves than in the sensory nerves at the proximal end after injury, but its expression was greater in the sensory nerves at 2 weeks. Semaphorin 3A expression was higher in the motor nerves than in the sensory nerves at 3 days and 1 week after injury. Nerve cell adhesion molecule L1 and semaphorin 3A expressions at the distal end were higher in the motor nerves than in the sensory nerves at 3 days, 1 and 2 weeks. Immunohistochemical staining results showed that nerve cell adhesion molecule L1 expression at the proximal end was greater in the sensory nerves than in the motor nerves; semaphorin 3A expression was higher in the motor nerves than in the sensory nerves at 2 weeks after injury. Taken together, these results indicated that nerve cell adhesion molecules L1 and semaphorin 3A exhibited different expression patterns at the proximal and distal ends of sensory and motor nerves, and play a coordinating role in neural chemotaxis regeneration.
authors.affiliation: Jiangsu Key Laboratory of Neuroregeneration, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China.
authors.forename: Qian-Ru
authors.initials: QR
authors.lastname: He
authors.affiliation: Jiangsu Key Laboratory of Neuroregeneration, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Cong
authors.affiliation: Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China.
authors.forename: Qing-Zhong
authors.initials: QZ
authors.lastname: Chen
authors.affiliation: Jiangsu Key Laboratory of Neuroregeneration, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China.
authors.forename: Ya-Feng
authors.initials: YF
authors.lastname: Sheng
authors.affiliation: Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Li
authors.affiliation: Jiangsu Key Laboratory of Neuroregeneration, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Jiangsu Key Laboratory of Neuroregeneration, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu Province, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Ding
authors.affiliation: Affiliated Hospital of Nantong University, Nantong, Jiangsu Province, China.
authors.forename: Yan-Pei
authors.identifier: 0000-0002-4847-9669
authors.initials: YP
authors.lastname: Gong
keywords: chemotaxis regeneration; motor nerve; nerve regeneration; neural cell adhesion molecule L1; neural regeneration; peripheral nerve injury; semaphorin 3A; sensory nerve