Quantification of myoglobin deoxygenation and intracellular partial pressure of O2 during muscle contraction during haemoglobin-free medium perfusion

フォーマット:

論文

責任表示:

Takakura, Hisashi ; Masuda, Kazumi ; Hashimoto, Takeshi ; Iwase, Satoshi ; Jue, Thomas

言語:

英語

出版情報:

Wiley-Blackwell, 2010-05-01

著者名:

• Takakura, Hisashi
• Masuda, Kazumi
• Hashimoto, Takeshi
• Iwase, Satoshi
• Jue, Thomas

掲載情報:

Experimental Physiology

ISSN:

0958-0670      

巻:

95

通号:

5

開始ページ:

630

終了ページ:

640

バージョン:

author

概要:

金沢大学人間社会研究域人間科学系<br />Although the O2 gradient regulates O2 flux from the capillary into the myocyte to meet the energy demands of contracting muscle, intracellular O2 dynamics during muscle contraction remain unclear. Our hindlimb pe … rfusion model allows the determination of intracellular myoglobin (Mb) saturation () and intracellular oxygen tension of myoglobin () in contracting muscle using near infrared spectroscopy (NIRS). The hindlimb of male Wistar rats was perfused from the abdominal aorta with a well-oxygenated haemoglobin-free Krebs-Henseleit buffer. The deoxygenated Mb (Δ[deoxy-Mb]) signal was monitored by NIRS. Based on the value of Δ[deoxy-Mb], and were calculated, and the time course was evaluated by an exponential function model. Both and started to decrease immediately after the onset of contraction. The steady-state values of and progressively decreased with relative work intensity or muscle oxygen consumption. At the maximal twitch rate, and were 49% and 2.4 mmHg, respectively. Moreover, the rate of release of O2 from Mb at the onset of contraction increased with muscle oxygen consumption. These results suggest that at the onset of muscle contraction, Mb supplies O2 during the steep decline in, which expands the O2 gradient to increase the O2 flux to meet the increased energy demands. © 2010 The Physiological Society. 続きを見る

URL:

http://hdl.handle.net/2297/24446