Mochizuki Seiichi, Miyasaka Takehiro, Goto Masami, Ogasawara Yasuo, Yada Toyotaka, Akiyama Maki, Neishi Yoji, Toyoda Tomohiko, Tomita Junko, Koyama Yuji, Tsujioka Katsuhiko, Kajiya Fumihiko, Akasaka Takashi, Yoshida Kiyoshi
Department of Medical Engineering, Kawasaki Medical School, 577 Matsushima, Kurashiki, 701-0192, Okayama, Japan.
Biochem Biophys Res Commun. 2003 Jun 27;306(2):505-8. doi: 10.1016/s0006-291x(03)00985-9.
Intra-aortic measurement of nitric oxide (NO) would provide valuable insights into NO bioavailability in systemic circulation and vascular endothelial function. In the present study, we thus developed a catheter-type NO sensor to measure intra-aortic NO concentration in vivo. An NO sensor was encased and fixed in a 4-Fr catheter. The sensor was then located in the thoracic aorta via the femoral artery through a 7-Fr catheter to measure intra-aortic plasma NO concentration in vivo in anesthetized dogs. Infusion of acetylcholine (10 microg/kg) increased base-to-peak plasma NO level in the aorta by 2.4+/-0.4 nM (n=7). After 20-min infusion of N(G)-methyl-L-arginine (NO synthase inhibitor), changes in plasma NO concentration in response to acetylcholine were attenuated significantly (1.8+/-0.4 nM, P<0.003, n=7). In conclusion, the newly developed catheter-type NO sensor successfully measured acetylcholine-induced changes in intra-aortic plasma concentration of endothelium-derived NO in vivo and demonstrated applicability to direct evaluation of intravascular NO bioavailability.
