Synchronous detection of vascular tension and nitric oxide release in pulmonary artery: A combined application of confocal wire myograph with confocal laser scanning microscopy

• Published in: Vascular 2020-10, Vol.28 (5), p.619-628
• Main Authors: Zhuang, Xiao-Ling, Zhu, Zhuang-Li, Zhu, Jie-Ling, Lai, Su-Mei, Gui, Long-Xin, Lin, Mo-Jun
• Format: Article
• Language: English
• ISSN: 1708-5381; 1708-539X
• DOI: 10.1177/1708538120917555

Objectives To detect the vascular tension and nitric oxide (NO) release synchronously in mice pulmonary artery, we perform two experiments and present a novel application of confocal wire myograph coupled with the confocal laser scanning microscopy. Methods In the first experiment, viable endothelium-intact mouse pulmonary artery (outer diameter 100–300 μM) rings underwent a one-hour preincubation with a NO-specific fluorescent dye, 4-amino-5-methylamino-2′,7′-difluorofluorescein diacetate Calbiochem (2.5 μM), and then precontracted with phenylephrine (Phen, 10−6 M), and subsequently dilated in acetylcholine (ACh, 10−6 M – 10−4 M). The endothelium-dependent vasorelaxation and NO generation in pulmonary artery rings were simultaneously recorded. In the second experiment, after 30-min incubation with the former NO fluorescent dye, the qualified pulmonary artery rings were co-incubated for another 30 min with a nitric oxide synthase inhibitor, 10−4 M Nω-nitro-L-arginine-methyl-ester (L-NAME), and then pretreated with Phen (10−6 M) followed by ACh (10−5 M). The Ach-induced vasodilation and NO release were recorded simultaneously. Results ACh (10−6 M – 10−4 M) promoted pulmonary artery relaxation and intracellular NO release in a dose-dependent manner. Additionally, L-NAME (10−4 M) significantly attenuated the vasodilatation and the intracellular NO release. Conclusions This combined application visually confirms that the synchronous changes in Ach induced vasodilation and NO release, which provides a new method for cardiovascular research.