Genome Wide Analysis Of Rat Skeletal Muscle Hypertrophy Nder Restriction Of Blood Flow(The Section Of Immunohistochemistry)

Blood flow restriction(BFR)with the low-intensity resistance training can induce skeletal muscle hypertrophy.It can produce a similar effective to those observed with high intensity resistance training.Previously,a rat model of skeletal muscle hypertrophy by limiting blood flow of the soleus has been successful developed.However,the potential molecular mechanisms are largely unknown.Objective:The objective of this study is to better understand the mechanisms of regulating human muscle hypertrophy induced by BFR and reveal possible therapeutic targets for atrophy on clinic by identifying unique genes of differentially expressed during rat muscle hypertrophy via microarray.Methods:Sprague-Dawley ratswere randomly separatedin two groups(6animals/group):control group(Con),experimental group(BFR).According to the modeling methods of Shouyu ect,the rat right hindlimbs above the knee near femoral joint of the experimental groupwere cut off blood flow with a rubber band for 30 minutes,2 times/week/2 weeks.The control group did not receive any treatment.Soleus were collected at 2 weeks post-ischemia and used for microarrayand immunohistochemistry.Results were compared with the normal soleus.Result 1:Wedemonstrate that skeletal muscle hypertrophy under BFR is characterized by increasing protein synthesis and inhibiting protein degradation Specifically,PI3K/AKT and MAPK pathways act as a positive regulator in controlling protein synthesis,whereas ubiquitin-proteasome acts as a negative regulator.2.We demonstrate the modulation of eight novel genes,Chrna1,Pla2g2a,Stap2,Trib3,Cacnb1,and Hspbapl,Ipo5 and Smc4 in our muscle hypertrophy model.Among the eight genes,Chmal,Pla2g2a,Stap2,Trib3,Cacnb1,and Hspbaplare up-regulated genes,while lpo5 and Smc4 are down-regulated genes.