Noninvasive measurement of temperature and fractional dissociation of imidazole in human lower leg muscles using 1H-nuclear magnetic resonance spectroscopy

• Published in: Journal of applied physiology (1985) 2005-01, Vol.98 (1), p.282-287
• Main Authors: Yoshioka, Yoshichika, Oikawa, Hiroshi, Ehara, Shigeru, Inoue, Takashi, Ogawa, Akira, Kanbara, Yoshiyuki, Kubokawa, Manabu
• Format: Article
• Language: English
• Subjects: Adult; Animals; Biological and medical sciences; Body Temperature - physiology; Fundamental and applied biological sciences. Psychology; Humans; Hydrogen-Ion Concentration; Imidazoles - metabolism; In Vitro Techniques; Lower Extremity - physiology; Magnetic Resonance Spectroscopy - methods; Male; Muscle, Skeletal - physiology; Muscular system; NMR; Nuclear magnetic resonance; Reproducibility of Results; Sensitivity and Specificity; Striated muscle. Tendons; Swine; Temperature; Thermography - methods; Vertebrates: osteoarticular system, musculoskeletal system
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/japplphysiol.00437.2004

Departments of 1 Physiology II, 2 Radiology, and 3 Neurosurgery, School of Medicine, Iwate Medical University, Morioka; and 4 High Field Magnetic Resonance Imaging Research Institute, Iwate Medical University, Takizawa, Japan Submitted 26 April 2004 ; accepted in final form 15 September 2004 The temperature change of the fractional dissociation of imidazole ( -imidazole) in resting human lower leg muscles was measured noninvasively using 1 H-nuclear magnetic resonance spectroscopy at 3.0 and 1.5 T on five normal male volunteers aged 30.6 ± 10.4 yr (mean ± SD). Using 1 H-nuclear magnetic resonance spectroscopy, water, carnosine, and creatine in the muscles could be simultaneously analyzed. Carnosine contains imidazole protons. The chemical shifts of water and carnosine imidazole protons relative to creatine could be used for estimating temperatures and -imidazole, respectively. Using the chemical shift, the values of temperature in gastrocnemius (Gast) and soleus muscles at ambient temperature (21–25°C) were estimated to be 35.5 ± 0.5 and 37.4 ± 0.6°C (means ± SE), respectively (significantly different; P < 0.01). The estimated values of -imidazole in these muscles were 0.620 ± 0.007 and 0.630 ± 0.013 (means ± SE), respectively (not significant). Alternation of the surface temperature of the lower leg from 40 to 10°C significantly changed the temperature in Gast ( P < 0.0001) from 38.1 ± 0.5 to 28.0 ± 1.2°C, and the -imidazole in Gast decreased from 0.631 ± 0.003 to 0.580 ± 0.011 ( P < 0.05). However, the values of -imidazole and the temperature in soleus muscles were not significantly affected by this maneuver. These results indicate that the -imidazole in Gast changed significantly with alternation in muscle temperature ( r = 0.877, P < 0.00001), and its change was estimated to be 0.0058/°C. alphastat; pH; carnosine; gastrocnemius Address for reprint requests and other correspondence: Y. Yoshioka, Dept. of Physiology II, School of Medicine, Iwate Medical Univ., Morioka 020-8505, Japan (E-mail: yyoshiok{at}iwate-med.ac.jp )