Submitted on March 3, 2005
Accepted on July 17, 2006
The role of ascorbic acid and exercise in chronic ischemia of skeletal muscle in rats
Theodoros Loizidis1, Antonia Sioga2, Louiza Economou2, Athanasios Frosinis1, Antonios Kyparos3, Anastasia Zotou4, and Maria Albani1*
1 Physiology, Faculty of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
2 Histology - Embryology, Faculty of Medicine Aristotle University of Thessaloniki, Thessaloniki, Greece
3 Laboratory of Physiology, Physical Education and Sports Science, Aristotle University of Thessaloniki, Thessaloniki, Greece
4 Analytical Chemistry, Chemistry, Aristotle University of Thessaloniki, Thessaloniki, Greece
* To whom correspondence should be addressed. E-mail: albani{at}med.auth.gr.
This study investigates the effects of peripheral arterial insufficiency, exercise and vitamin C on muscle performance, cross sectional area and ultrastructural morphology in extensor digitorum longus (EDL) and soleus (SOL) muscles in rats.
Adult Wistar rats were assigned to ischemia (isch), ischemia-exercised (exe), ischemia-vitamin C (vit C), and ischemia-exercise-vitamin C (vit C + exe) group. Ischemia was achieved via unilateral ligation of the right common iliac artery. Contralateral muscles served as controls. Exercise protocol consisted of 50-min intermittent level running performed every other day for 5 days. Vitamin C (100 mg/kg BW, i.p) was administered on a daily basis.
In EDL muscle, ischemia reduced muscle strength, which was not recovered after Vit C administration. Exercise induced the most severe structural damage and cross sectional area decrease, yet the reduction in tetanic tension was not significant. Exercise and vitamin C preserved ischemia-induced EDL muscle tetanic tension.
In the soleus muscle, a significant reduction in single twitch tension after vitamin C administration was found, whereas the tetanic force of the ischemic soleus was not significantly decreased in any group. Ischemic SOL muscles cross sectional area was reduced in all, but the exe, groups. In SOL, muscle strength was reduced in Vit C group, and mean cross sectional area of ischemic SOL muscles was reduced in all groups except of the exe group.
These results illustrate that mild exercise, combined with low dose of vitamin C, may have beneficial effects on ischemic EDL muscle with a smaller effect on the soleus muscle.
