Contractile responses to angiotensin II. Ang II induced a concentration-dependent contraction at lower concentrations (10 212 to 10 28 mol/L, Figure 1B) and dilatation at higher concentrations (3?10 28 to 3?10 26 mol/L, **data** not shown). These responses occurred in both male and female arteries after organ culture, but the male arteries were more sensitive to Ang II resulting in concentration-response curves that were significantly different (P,0.05, Figure 1B). pEC 50 for Ang II-mediated contraction was higher for males compared to females, as shown by a concentration-response curve further to the left for males (P = 0.09, Figure 1B, Table 1). The maximum contraction to Ang II was not different between male and female arteries.