2.6. Arterial Reactivity

Aortas and first branches of superior mesenteric arteries were collected in physiological saline solution (in mM: 130 NaCl, 5.6 KCl, 1 MgCl₂, 2 CaCl₂, 11 glucose, 10 Tris, pH 7.4 with HCl), cleaned, and cut in 2 mm long rings. Arterial rings were then mounted on multichannel isometric myograph, bathed in Krebs-Henseleit solution at 37°C, bubbled with 95% O₂–5% CO₂, and connected to a force transducer (Pioden controls Ltd, Canterbury, UK for aortic rings; Danish Myo Technology; Aarhus, Danemark, for mesenteric artery rings). After equilibration, the contractile response to KCl 60 mM was measured. Endothelial function was assessed by measuring the relaxing response to cumulative doses of carbachol (CCh, 1 nM −10 μM) of rings precontracted by phenylephrine (PhE, 1 μM). Digital data were recorded by a MacLab/4e recorder and analyzed using a LabChart v7 software (AD Instruments, Paris, France).