Effects of immobilization and whole-body vibration on rat serum Type I collagen turnover

OBJECTIVE: The aim of this study was to investigate the effects of short-term, high-magnitude whole-body vibration (WBV) on serum type I collagen turnover in immobilized rats. MATERIALS AND METHODS: Thirty Wistar albino rats were randomly divided into the following 5 groups: immobilization (IS), immobilization + remobilization (IR), immobilization + WBV (IV), control (C), and WBV control (CV). Immobilization was achieved by casting from the crista iliaca anterior superior to the lower part of the foot for 2 weeks. The applied WBV protocol involved a frequency of 45 Hz and amplitude of 3 mm for 7 days starting a day after the end of the immobilization period. Serum type I collagen turnover markers were measured by using ELISA kits. RESULTS: Serum NH2-terminal propeptide of type I collagen (PINP) levels were significantly lower in the immobilization groups (p < 0.02) compared with the control groups. Although WBV improved PINP levels in the control groups, there were no differences in PINP levels among the immobilization groups. Similarly, serum COOH-terminal telopeptide of type I collagen (CTX) levels were higher in the WBV controls than their own controls (p < 0,05). Immobilization led to deterioration of tendon tissue, as observed by histopathological analysis with a transmission electron microscope. CONCLUSION: Although 1 week of WBV had a positive effect on type I collagen turnover in controls, it is not an efficient method for repairing tissue damage in the early stage following immobilization.