The Study of the Effect of A Long Term Endurance Activity on Cardiac Structure and Expression of Mir-133 in Rats

Endurance training causes cardiac remodeling, one of the factors that adjusting expression of more genes of heart is miR-133. The aim of this study was to evaluate the effect of endurance training on miR-133 expression in wistar rats’ heart. In this experimental study, 14 rats were housed under controlled conditions for 4 weeks, after familiarization they were randomly assigned to control (7 rats) and experimental (7 rats) groups. The experimental group performed 14 weeks, 6 session per week an endurance training program (that gradually reached to 60 min and 30 m/min) on treadmill. 48 hours after the end of the last session, all animals were anesthetized and sacrificed. Then, the their heart were removed and after tissue homogenization of left ventricle, and RNA extraction, and cDNA synthesis, the expression level of left ventricle miR-133 were measured by using Real-Time PCR. The rate of miR-133 expression was evaluated by using t-test at p≤ 0.05 level.  This study was approved in Research Ethics Committee of Lorestan University with the code 1396345.52 After 14 weeks endurance training, the expression of heart miR-133 in experimental group was significantly increased (p=0.007) than control group which coincided with increase of the rate of left ventricular mass to weight body (p=0.012). Regarded to structural changes of heart, it seems the part of heart adaptation to endurance exercise caused by increase in miR-133 expression.