Cyclic muscle twitch contraction inhibits immobilization-induced muscle contracture and fibrosis in rats. (3rd September 2017)

• Record Type: Journal Article
• Authors: Yoshimura, Ayana; Sakamoto, Junya; Honda, Yuichiro; Kataoka, Hideki; Nakano, Jiro; Okita, Minoru
• Is Part Of: Connective tissue research. Volume 58:Number 5(2017)
• Page Start: 487
• Page End: 495
• Publication Date: 2017-09-03
• Subjects: Cyclic muscle twitch contraction -- hypoxia -- immobilization -- muscle fibrosis -- transforming growth factor-β1; Connective tissues -- Periodicals; 616.770072
• DOI: 10.1080/03008207.2016.1257004
• Languages: English
• ISSNs: 0300-8207

Abstract

ABSTRACT: We investigated the effects of cyclic muscle twitch contraction caused by neuromuscular electrical stimulation (NMES) on immobilization-induced muscle contracture and fibrosis in rats. Twenty-nine rats were divided into control, immobilization, and immobilization with muscle contraction groups. The ankle joints of the immobilization and muscle contraction rats were fixed in full plantar flexion with a plaster cast for 4 weeks. In the muscle contraction group, cyclic muscle twitch contraction of the soleus muscle was induced using a commercial device (1 Hz, 4 ± 2 mA, 60 min/day, 5 times/week) with the ankle joint immobilized. The dorsiflexion range of ankle joint motion in the muscle contraction group was significantly greater than that in the immobilization group. The expressions of fibrosis-related genes (i.e., hypoxia inducible factor-1α, transforming growth factor-β1, α-smooth muscle actin, and types I and III collagen) were significantly decreased in the muscle contraction group compared to the immobilization group. The fluorescence intensities of type I and type III collagen in the perimysium and endomysium in the muscle contraction group were significantly decreased compared to the immobilization group. These results suggest that cyclic muscle twitch contraction induced by NMES might alleviate skeletal muscle fibrosis, reducing immobilization-induced muscle contracture.