Ros, Of Mptp-mediated Muscle Cell Apoptosis In Rats Lost Nerve Skeletal Muscle Atrophy In Experimental Research

Objective To study the expression of reactive oxygen species (ROS), mitochondrial permeability transition pore (MPTP) in denervated skeletal muscle atrophy and its correlation of cell apoptosis,and explore specific molecular mechanism in denervated skeletal muscle.Methods A total of thirty Vista rats that have 200-250 weight randomly divided into five group: control group (sham operation),2 days group, 7 days group, 14days group, 28 days group. Standard model of denervated gastrocnemius muscle was established. The rats were executed by vertebrae dislocation method. Microsurgical technique was used to dissociate the denervated gastrocnemius and weighting its wet weight. The skeletal muscle of single cell suspension immediately did by 1/3 denervated gastrocnemius muscle samples. After labeled by DCFH-DA ,The content of ROS in the gastrocnemius were detected by flow cytometry (FCM).Denervated gastrocnemius muscle samples were taken 1/3 to do frozen section and labeled by dye .The mitochondrial permeability transition pore in the gastrocnemius were detected by fluorescence microscope; After the remaining 1/3 of denervated gastrocnemius muscle samples did the frozen section, the apoptotic cells in atrophic muscle were detected by TUNEL.Results Compared with the control group after denervation, the expression of ROS, the opening of MPTP and the apoptosis of gastrocnemius were continued to increase(< 28 days), and the expression of each group were significantly higher (P <0.05).Furthermore the expression of ROS had a positive correlation with the opening of MPTP ( r=0.884,P<0.01) and the ratio of apoptosis (r=0.893, P<0.01), the opening of MPTP had a positive correlation with the ratio of apoptosis (r=0.927,p<0.01), and had a negtively correlation with the ratio of muscle wet weight( r=-0.907,P<0.01).Conclusion The Vistar rats in the early atrophy of denervated skeletal muscle, with the extension of denervation, the phenomenon of skeletal muscle atrophy were aggravating, the expression of ROS, the opening of MPTP and the apoptosis of gastrocnemius were continued to increase, the expression of each group were significantly higher than the control group. In the process of denervated skeletal muscle atrophy, ROS and MPTP what are upstream regulatory factors in the apoptosis pathway may regulate skeletal muscle atrophy after denervation, that play a role in the course of skeletal muscle atrophy,The specific mechanism need to be lucubrated by step.