Expression of Protein Kinase B Isoforms in the Gastrocnemius Muscle of Rats at Different Ages / 中国微创外科杂志

ABSTRACT

Objective To study the expression of protein kinase B (Akt/PKB) isoforms in the gastrocnemius muscle of rats at different ages. Methods The expression levels of mRNA and protein of three Akt isoforms in the gastrocnemius muscle of 30-month-old and 6-month-old rats were detected respectively by RT-PCR and Western blotting. Data were analyzed statistically. Results (1) The levels of Akt1 and Akt2 mRNA in the 30-month-old rats was significantly higher than those in the 6-month-old rats (t=7.124, P=0.000; t=2.598, P=0.021), however, no significant difference was found in the level of Akt3 mRNA between the two groups (t=0.460, P=0.653) . (2) The level of Akt-Thr308 phosphorylation in the 30-month-old rats was significantly lower than that in the 6-month-old rats (t=-9.861, P=0.000), while the level of Akt2 protein in the 30-month group was significantly higher than that in the younger rats (t=7.522, P=0.000). No significant differences were detected in the levels of Akt1 and Akt3 proteins between the two groups (t=0.469, P=0.646; t=0.058, P=0.955). Conclusion The expression levels of three Akt isoforms in the gastrocnemius muscle of rats change with age, suggesting that the three isoforms of Akt have different functions in the gastrocnemius muscle metabolism of rats at different ages.