Figure 4. The response to UK14,304 in control middle cerebral arteries and in middle cerebral arteries after the endothelium was removed by forcing 8 ml of air through the lumen of the vessels. The resting diameters were 254+/-6 micro meter and 212+/-16 micro meter (n = 7) for middle cerebral arteries with and without endothelium, respectively. *P < 0.05 compared to control.