Fig. 4
Norepinephrine-induced vascular smooth muscle cell (VSMC) intracellular Ca2+ responses and membrane depolarizations are reduced in breast cancer feed arteries compared to control arteries. a, b Normalized VSMC intracellular Ca2+ responses during stimulation with norepinephrine (a) (n = 7) or endothelin-1 (b) (n = 6). Curves are results of least-squares fits to sigmoidal functions and compared using extra-sum-of-squares F tests. c VSMC membrane potentials (n = 7) at rest and in the presence of 10 μmol/L norepinephrine or 100 nmol/L endothelin-1. Data were compared by repeated measures two-way analysis of variance followed by Sidak’s post-hoc test. *P < 0.05, ***P < 0.001, NS: not significantly different vs. control