Figure 2. (A) The percent change in the diameter of the rat middle cerebral artery with increasing concentrations of UK14,304 in MCAs with flow (100 micro liter/min) and without flow (diameter 239+/-13 micro meter, n = 8 middle cerebral arteries). The transmural pressure was maintained at 85 mmHg in all middle cerebral arteries. There was no significant difference in the dilation produced by UK14,304 in middle cerebral arteries with flow or without flow. (B) The percent change in diameter for two consecutive UK14,304 dose-response curves (diameter 233 +/-8 micro meter, n = 6 middle cerebral arteries). There was no significant difference in the dilation produced by UK14,304 between the first (control 1) and second (control 2) curves.