The Effect of Intermittent Training and the Role of Age on Monocarboxylate Transporter (MCT1 and MCT4) Genes Expression and Lactate Level in Skeletal Muscles of Wistar Rat

In ageing, physiological changes occur along with decreased MCT1 and MCT4 genes expression in skeletal muscles, howerver, this reduction can be modified by physical activity. The purpose of this study was to determine the effect of intermittent training and the role of age on MCT1 and MCT4 genes expression and lactate level in skeletal muscles of rat. In this experimental study, forty male rats were divided into two age groups of old (age, 27 months; weight, 389±31g) and young (age, 3 months, weight, 224±14g). Each group was randomly devided into two groups of experimental (n=10) and control (n=10). Training protocol was done intermittently on a treadmill, consisting of 10 bouts of 4 min running interspersed by 2 min of active rest, 6 times a week for 8 weeks. The rats were anesthetized, 24 hours after the last session of training, and their soleus (SOL) and extensor digitorum longus (EDL) muscles of toes were removed. The lactate level was measured by enzymatic method and the gene expression by real-time PCR. Data were analyzed using one way-ANOVA, post-hoc Tukey, and t tests. The significance level was considered p<0.05. A significant reduction was observed in the lactate level of SOL and EDL muscles in the two experimental group (old and young) (p<0.05). In both age groups. MCT1 and MCT4 mRNA increased in the muscles. No significant difference was observed in gene expression in the two age groups. These results is indicative of the effect of intermittent training on the increase of MCT1 and MCT4 gene expression in skeletal muscles, and show that this effect is independent of age. Also, increased expression of MCT genes is of great importance for lactate clearance.