Vascular reactivity
To assess the effect of both CS-exposure and ebselen treatment on vessel
function, thoracic aorta was excised from the mice and all perivascular
fat removed. Vessels were placed into carbogen-bubbled (95%
O2, 5% CO2) cold Krebs buffer
(composition in mmol/L: NaCl 119, KCl 4.7, MgSO4 1.17,
NaHCO3 25, KH2PO4 1.18,
CaCl2 2.5, glucose 5.5). The aortae were cut into four 2
mm rings and mounted onto the pins of the myograph system (Danish Myo
Technology A/S, Model 610M) with the resting tension increased to 5mN
which was determined to give an effective arterial wall pressure of
~100mmHg (13.3kPa) thus mimicking in vivoconditions. Following a 30-minute equilibration, aortic rings were
exposed to 0.5 x 10-3M of the thromboxane A2 agonist
U46619 (Cayman Chemical, USA) to induce the maximal vascular
contraction, defined as 100%. In each ring, both endothelial integrity
and smooth muscle function were assessed using cumulative doses of
acetylcholine (ACh, 1x10-8M to
1x10-5M) (Thermo Fisher Scientific, USA) and sodium
nitroprusside (SNP, 1x10-8M to
1x10-5M) (Thermo Fisher Scientific, USA) respectively
in sub-maximally contracted aorta (50-60% of maximal U46619
contraction) with all experiments ran in duplicate and compared to sham
or sham + vehicle treated mice.