title: Morphological differences in skeletal muscle atrophy of rats with motor nerve and/or sensory nerve injury.
abstract: Skeletal muscle atrophy occurs after denervation. The present study dissected the rat left ventral root and dorsal root at L4-6 or the sciatic nerve to establish a model of simple motor nerve injury, sensory nerve injury or mixed nerve injury. Results showed that with prolonged denervation time, rats with simple motor nerve injury, sensory nerve injury or mixed nerve injury exhibited abnormal behavior, reduced wet weight of the left gastrocnemius muscle, decreased diameter and cross-sectional area and altered ultrastructure of muscle cells, as well as decreased cross-sectional area and increased gray scale of the gastrocnemius muscle motor end plate. Moreover, at the same time point, the pathological changes were most severe in mixed nerve injury, followed by simple motor nerve injury, and the changes in simple sensory nerve injury were the mildest. These findings indicate that normal skeletal muscle morphology is maintained by intact innervation. Motor nerve injury resulted in larger damage to skeletal muscle and more severe atrophy than sensory nerve injury. Thus, reconstruction of motor nerves should be considered first in the clinical treatment of skeletal muscle atrophy caused by denervation.
authors.affiliation: Department of Orthopedics, Third Affiliated Hospital of Nantong University, Wuxi 214041, Jiangsu Province, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Neural Regeneration of Jiangsu Province, Nantong University, Nantong 223001, Jiangsu Province, China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Lv
authors.affiliation: Central Laboratory, Third Affiliated Hospital of Nantong University, Wuxi 214041, Jiangsu Province, China.
authors.forename: Shengyang
authors.initials: S
authors.lastname: Jiang
authors.affiliation: Laboratory of Mechanical Biology and Medical Engineering, Shanghai Jiao Tong University School of Medicine, Shanghai 200030, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Yan
authors.affiliation: Central Laboratory, Third Affiliated Hospital of Nantong University, Wuxi 214041, Jiangsu Province, China.
authors.forename: Junming
authors.initials: J
authors.lastname: Sun
authors.affiliation: Central Laboratory, Third Affiliated Hospital of Nantong University, Wuxi 214041, Jiangsu Province, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.affiliation: Central Laboratory, Third Affiliated Hospital of Nantong University, Wuxi 214041, Jiangsu Province, China.
authors.forename: Donglin
authors.initials: D
authors.lastname: Jiang
keywords: motor end plate; muscular atrophy; neural regeneration; rats; simple nerve injury; ultrastructure