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The influence of tissue blood flow volume on energy metabolism in masseter muscles
Kazuki Okada1, Taihiko Yamaguchi, Kosetsu Komatsu
1Dept. of Gnathofunctional Medicine, Graduate School of Dental Medicine, Hokkaido University, West 7 North 13, Kita-ku, Sapporo 060-8586, Japan. kokada@den.hokudai.ac.jp
Abstract:
This study investigated the energy metabolism of masseter muscles by 31P-Magnetic Resonance Spectroscopy (MRS) during increased blood flow induced by hot pack application to clarify the influence of changes in blood flow on muscle fatigue. Twelve healthy subjects with no history of muscle pain in the masticatory system participated in this study. The 31P-MRS measurements were performed before and after hot pack application and the ratio of phosphocreatine (PCr) acting as the energy source to reproduce ATP to beta-ATP, the PCr/beta-ATP ratio, was analyzed. Results showed that PCr/beta-ATP ratios increased significantly by an average of 22.4% after the hot pack application. The results suggest that changes in blood flow volume influence the energy metabolism in masseter muscles and that blood flow increases due to the hot pack cause higher energy levels in masseter muscles and offer an advantageous condition for preventing and relieving muscle fatigue.
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