Figure 3.

Effect of Y27632 on contraction pre-induced by U46619. (A) The upper (larger) experimental record is representative of contraction induced by 10 nM U46619 followed by relaxation in response to Y27632. The lower trace on the same plot is the effect of 10 μM Y27632 on another vessel segment in the absence of U46619. Contraction is expressed as a percentage of that evoked by 80 mM K⁺. (B) Mean±s.e.mean Y27632-induced relaxation of U46619-evoked tone in endothelium-intact vessels given as a percentage 80 mM K⁺-evoked contraction (EC₅₀ 1.67±0.22 μM, n=6). (C) Effect of Y27632 (1 and 10 μM) and GF 109203X on baseline tension in the absence of U46619 (n=4 in each group). Data points are mean±s.e.mean as a percentage of the maximum contractile responses to 80 mM K⁺ (*P=0.044, ^**P=0.0048). Experiments were performed in the presence of 10 μM diltiazem.