2008年3月
Nitric oxide generation directly responds to ultrasound exposure.
Ultrasound in medicine & biology
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- 巻
- 34
- 号
- 3
- 開始ページ
- 487
- 終了ページ
- 93
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
Recently, several reports have been published on ultrasonic vascular dilation produced with relatively low-frequency ultrasound. It has been speculated that nitric oxide (NO) is an important factor for this ultrasonic vascular dilation. However, a quantitative relationship between the ultrasound intensity and NO generation was not clarified in these reports. We investigated the quantity of NO generated by various ultrasonic intensities by means of real-time measurement of NO concentration in the adductor muscles of the thigh of New Zealand white rabbits exposed to a continuous-wave ultrasound (490 kHz). In the quantitative relationship between NO generation and ultrasonic intensity, the percent increase in NO concentration was 1.25% +/- 1.25%, 10.6% +/- 2.9% and 20.1% +/- 3.5%, with the maximum muscle temperature increase 0.5 +/- 0.2 degrees C, 0.7 +/- 0.2 degrees C, and 0.8 +/- 0.3 degrees C at the ultrasonic intensity (SPTA) of 0.21, 0.35 and 0.48 W/cm(2), respectively. The effect of ultrasound on NO generation was intensity-dependent with a progressive increase from 0.21 W/cm(2) to 0.48 W/cm(2) without significant thermal effect. Ultrasonic NO generation was partially reduced by NOS inhibitor of L-NMMA, clarifying that ultrasound can activate both NOS-dependent and NOS-independent NO generation. These new findings provided scientific basis for ultrasonic vasodilatation and support the potentiality of a new ultrasonic technology for the treatment and prevention of the ischemic tissue based on the new concept of NO generated angiogenesis. (E-mail: furuhata@jikei.ac.jp).
- リンク情報
- ID情報
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- ISSN : 0301-5629
- PubMed ID : 17933454