Wire myography
Aortic rings where integrin α4 and/or α9 were inhibited were incubated with either BOP or blocking antibodies overnight at 37 °C in a 5% CO2 incubator in DMEM basal media. Contractile force recordings were made from ≤2 mm ring segments of aortic rings mounted at 1.2 mN tension in a Mulvany-Halpern wire myograph (Danish Myo Technology). The bath solution contained (mmol/L): NaCl 136, KCl 5, MgSO4 1.2, CaCl2 1.8, glucose 5, mannitol 15, HEPES 10, NaH2PO4 0.5, Na2HPO4 0.5 pH 7.4. NaCl was reduced to 81 mmol/L and replaced with 60 mmol/L KCl for the high K+ solution. Vessels were depolarised in high K+ solution 3 times prior to initiation of contractile studies. Pharmacological inhibitors (nifidepine (3 µM), BIM (I) (10 µM), or BOP (3 µM) were added directly to the organ bath, maintained at 37°C, 30 minutes prior to addition of vasoconstrictors (U46619, PE, UTP, ET-1).