Influence of Direct Current on the Cartilaginous Metabolism in vivo

Abstract

▼ Purpose: To evaluate the eff ects of direct current (DC) on the cartilaginous metabolism in an experimental osteoarthritis (OA) animal model. Materials and Methods: In a randomized, controlled trial, 45 animals were divided into 5 equal groups, each consisting of 9 rabbits. The 1 st group was the intact control group and the 2 nd group was the OA control group. The rabbits ' injured knee joints were treated with DC of diff erent intensities: 0.01 mA / cm 2 (group 3), 0.1 mA / cm 2 (group 4), and 0.2 mA / cm 2 (group 5). The content of collagen in the cartilage, the collagenase enzyme activity in the blood and the content of glycosaminoglycans (GAGs) in the cartilage tissue and in the blood were evaluated. Results: An increase of collagen in the cartilage after exposure to a DC intensity of 0.2 mA / cm 2 to 6.0 ± 0.5 μ g / g (group 5) was found, compared to 4.2 ± 0.3 μ g / g (OA control). Collagenase enzyme activity in the blood decreased to 5.1 ± 0.4 μ mol / l · h (group 5) in comparison with the OA control (6.8 ± 0.4 μ mol / l · h). The GAG content in the cartilage amounted to 8.7 ± 0.7 μ g / mg and to 6.4 ± 0.4 μ g / mg in group 5 and OA control, accordingly. The GAG content in the blood decreased from 0.066 ± 0.005 g / l (OA control) to 0.051 ± 0.004 g / l under DC infl uence of 0.2 mA / cm 2 (group 5). Conclusions: DC (0.2 mA / cm 2 ) locally stimulates the metabolic process in the cartilaginous tissue and systemically in the blood after OA in vivo, indicating the therapeutic mechanism of DC.