Effects Of Mechanical Tension On The Stress Transduction Signal Pathway YAP/Myocardin In Limb Arteries

Objective:To investigate the effect of slow and steady tensile stress on the expression of YAP and Myocardin in limb arterial vessels.Methods:1.75 male New Zealand rabbits were randomly selected to establish an animal model of stretch stress on the upper tibia of the hind limb.2.75 experimental rabbits were randomly divided into groups A,B and C.Group A was the experimental group,one side of the hind limb was lengthened by osteotomy.Group B was the negative control group,only bone osteotomy without extension,and group C was the blank control group without any treatment.Results:1.The Ilizarov systerm worked for 10 days and extended the postenior limb artery of New Zealand rabbits by 0.76 cm on average,with an average stretching ratio of 25.17%.2.HE staining showed that On days 8,10,12,16 and 19 after extemal fixation,the arterial tissue structure of the experimental group was complete,with no intima vascular damage,no necrosis of smooth muscle cells,and no inflammatory cell infiltration.3.WB and ELISA results showed that:?1?The YAP expression level in the experimental group was higher than that in the negative control group on day 8,10 and 12 after surgery,and the difference was statistically significant?P<0.05?.On day 16 and19 after surgery,there was no statistically significant difference in the expression level between the experimental group and the negative control group?P>0.05?.On the 8^th,10^thh and 12^thh day after the operation,the expression level of Myocardin in the experimental group was not statistically sinificant compared with that in the negative control group?P>0.05?.On the 16^thh and 19^thh day after the operation,the expression level of Myocardin in the experimental group was higher than that in the negative control group,and the difference was statistically significant?P<0.05?.?2?The expression levels of YAP and Myocardin on day 8,10,12,16 and 19 after the operation were compared between the negative control group and the blank control group.The difference between the negative control group and the blank control group was not statistically significant?P>0.05?.Conclusion:1.The limb artery can be prolonged by slowly stabilizing the tensile stress in one direction.2.The stress transduction signaling pathway YAP/Myocardin in vascular smooth muscle cells can be activated by slow and steady tensile stress in one direction.