Muscle Fiber Type Changes in Lumbrical Muscles at Early Stages of Chronic Nerve Compression

Muscle Fiber Type Changes in Lumbrical Muscles at Early Stages of Chronic Nerve Compression

Zhen-yu LIU[1];Jiang-hai CHEN[1];Zhen-bing CHEN[1];

【期刊名称】《当代医学科学(英文)》

【年(卷),期】2019(039)001

【摘要】Chronic nerve compression(CNC)neuropathy is a common disease in the clinic and provokes paraesthesia,or numbness at early stage.The changes in muscle fiber composition and motor nerve terminal morphology in distal muscles were studied in this study.A well-established CNC model was used to assess the changes in the muscles.Behaviors were measured by von Frey filament test The myosin heavy chain isoforms and neuromuscular junctions(NMJs)were stained by immunofluorescence to show the muscle fiber types composition and motor nerve terminals morphologic changes in the flexor digitorum longus(FDL)and lumbrical muscle.The fiber cross-sectional areas of different muscle fiber types were measured.The small-fiber degeneration of cutaneous nerve fibers was examined by detecting the protein gene product 9.5(PGP9.5)with immunofluorescence.At 2nd month after compression,the proportion of type I and type IIB fibers was markedly decreased,and that of type n A fibers was increased in the lumbrical muscle.There was no significant change in composition of muscle fiber types in FDL and NMJ morphology of FDL and lumbrical