Fig. 3From: Murine breast cancer feed arteries are thin-walled with reduced α1A-adrenoceptor expression and attenuated sympathetic vasocontractionMedia stress of breast cancer feed arteries is reduced compared to matched control arteries in response to norepinephrine and U46619 but not in response to endothelin-1 or depolarization with elevated extracellular K+ concentration ([K+]o). Media stress (wall tension divided by media thickness) during stimulation with 300 nmol/L endothelin-1 (a) (n = 19), 80 mmol/L K+o (b) (n = 16), 30 μmol/L norepinephrine (c) (n = 24), and 3 μmol/L U46619 (d) (n = 11). Experiments with elevated [K+]o were performed in the presence of 1 μmol/L phentolamine in order to avoid the effects of norepinephrine released from sympathetic nerve endings in response to depolarization. Data were compared by the paired two-tailed Student’s t test. Responses to U46619 were log-transformed before statistical comparison to achieve normal distribution. *P < 0.05, **P < 0.01, NS: not significantly different vs. controlBack to article page