EN
Twenty adult (8 to 10 months old) male New Zealand White rabbits were divided randomly into four equal groups. After preparation of each rabbit for surgical procedure, the right deep digital flexor tendon was crushed in a standard method. Then the limb was fixed with external coaptation for 7 d. The post-operative treatment in each group included: no treatment (CN), ascorbic acid, 100 mg.kg⁻¹, i.p. (AA), α -tocopherol, 20 mg.kg⁻¹, i.m. (AT), and both vitamins simultaneously (CM) for nine consecutive days. At the 13th d after surgery each rabbit was euthanized and tissues from the crushed tendon were prepared for ultrastructural evaluation by transmission electron microscopy. The median values of collagen fibril diameter in the AT group were the highest; group AA was more than the CN and CM groups; and group CM was the least. The results obtained indicated a significant positive effect of ascorbic acid and α-tocopherol on collagen fibril structural properties and tendon healing. However, combination of both vitamins had no synergistic effect on tendon healing and even significantly decreased the effect in comparison to each individual vitamin (P<0.05).