Figure 9.

Measurement of CaCl₂ concentration response curves, in the presence of ET-1 (100 nM), in aorta (a) and vena cava (b). Tissues were first incubated for 30 minutes in Ca²⁺-free buffer with 1 mM EGTA, then in Ca²⁺-free buffer (no EGTA) for 10 minutes before addition of 100nM ET-1. After plateau of any contraction to ET-1, tissues were incubated with vehicle (solid shapes) or 10 μM KB-R7943 (open shapes). Points represent mean ± SEM for the number of animals indicated in parentheses. Boxes represent the CaCl₂ concentration that is equivalent to that of physiological salt solution used in all other experiments. * = p<0.05 versus vehicle.