Teh Effect of Local anesthetic on Degeneration and Regeneration of the Experimentally Traumatized Striated Muscle

Kim, Nam Hyun; Lee, Seok Beom

Abstract

The repair of striated muscle after acute trauma occurs simultaneously by the regeneration of disrupted muscle and formation of connective scar. But, there had been no attention concerning effects of local anesthetics on the degeneration and regeneration process of the injured muscle. The author induced a constant contusion injury on the calf of rats. Lidocaine and/or epinephrine was intramuscularly injected at the site of injury. Morphological and histochemical observation was conducted and the results were as follows: 1. Traumatized striated muscle showed evidences of the healing process for upto 90 days. 2. Morphological and histochemical changes in the traumatized muscle became more severe after the injection of lidocaine and/or epinephrine. 3. Formation of collagenous scar tissue significantly increased after injection of lidocaine and/or epinephrine. Injection of lidocaine or epinephrine developed similar amount of scar after 15 days. 4. Cross section area of the regenerated muscle fibers decreased in the injection groups than in the control groups. Atrophy was significant on day 90 in all types of fiber after injection of the mixture of lidocaine and epinephrine, and in type B after injection of epinephrine. In conclusion, injection of the lidocaine and epinephrine inhibited regeneration of the traumatized striated muscle. Mixture of the drugs showed more inhibitory effect than a single drug.