K+ S6c     ET-1     n Emax,mN Emax,mN Emax, % pEC50 Emax,mN pEC50 Fresh 6 3.49 ± 0.59*** 0.02 ± 0.02*** 0.17 ± 0.17** N.A. 5.69 ± 0.70** 8.07 ± 0.13* 24 h 8 6.63 ± 0.47 6.07 ± 0.50 70.75 ± 4.80 8.69 ± 0.07 8.47 ± 0.46 8.32 ± 0.10 XeC 6 4.55 ± 0.39* 1.40 ± 0.27*** 21.83 ± 4.22** 8.70 ± 0.03 6.96 ± 0.42* 8.47 ± 0.06 KN93 6 0.45 ± 0.16*** 3.24 ± 0.60** 46.33 ± 10.54 8.77 ± 0.07 5.10 ± 0.68*** 8.30 ± 0.12 Emax values are presented as absolute values in mN or as percent of the ET-1-induced contraction and pEC50 values. Values are presented as mean ± SEM. Inhibitor was added prior to incubation. Fresh represents non-incubated arteries. * P < 0.05, ** P < 0.01, *** P < 0.001 compared to 24 h. N.A.= not available, XeC = xestospongin C.

Table 2: Contractile response induced by S6c and ET-1 in rat middle cerebral arteries.