2.4.5. Vascular reactivity studies
Descending thoracic aortic rings were removed from mice and suspended in
a wire myograph (model 610M, Danish Myo Technology, Aarhus, Denmark) for
isometric tension measurement as previously described by Toral et
al. (Toral et al., 2014). Krebs solution
(composition in mM: NaCl 118, KCl 4.75, NaHCO3 25,
MgSO4 1.2, CaCl2 2,
KH2PO4 1.2 and glucose 11) at 37°C was
used to fill the organ chamber and was subsequently gassed with 95%
O2 and 5% CO2 (pH 7.4). Length-tension
characteristics were acquired via the myograph software (Myodaq 2.01,
Danish Myotechnologies, Denmark) and the aortae were set to a tension of
5mN and equilibrated during 90 min. Thus, cumulative
concentration-response curves to acetylcholine (10-9M-10-5 M) were recorded for intact rings
pre-contracted by U46619 (10-8 M) in the absence or in
the presence of the selective nicotinamide adenine dinucleotide
phosphate (NADPH) oxidase inhibitor VAS2870 (10-5 M),
which was added 30 min before. Relaxant responses to acetylcholine were
expressed as a percentage of pre-contraction.