Vitamin E concentration in rat skeletal muscle and liver after exercise

The purpose of this study was to determine whether submaximal exercise significantly changes the concentration of vitamin E (alphaToc) in rat liver and skeletal muscle and to establish a time course for the return to basal levels. Male Sprague-Dawley rats, age 8 to 10 weeks, were randomly divided into sedentary control (Con) (n = 7) and exercise (n = 17) groups. Exercised animals ran 100 min on a motorized treadmill at approximately 70% VO2max for 3 consecutive days. They were then sacrificed immediately postexercise (0Post), 24 hr post (24Post), or 72 hr post (72Post). The gastrocnemius, red vastus lateralis (RV), white vastus lateralis (WV), and liver were excised and analyzed for alphaToc concentration by high-performance liquid chromotography utilizing electrochemical detection. We found that after 3 consecutive days of exercise, alphaToc was reduced in RV and WV at 0Post and 24Post but returned to control values by 72Post. Liver alphaToc content was not changed at 0Post but was significantly reduced at 24Post and 72Post. No significant changes in alphaToc were observed in the gastrocnemius in response to exercise. The data indicate that following an exercise-related decrease, skeletal muscle vitamin E concentration requires more than 24 hr to return to the preexercise concentration, and that the replenishment process may involve redistribution of vitamin E from liver to muscle.