Fig. 2.
Endothelium-dependent vasorelaxation of carotid arteries. The arteries were precontracted to approximate tension with phenylephrine (PE), and dose-responsive vasorelaxation was induced with acetylcholine (ACh). C, control group; CFO, chronic flow overload group; CFO+A, chronic flow overload group treated with apocynin; CFO+BH4, vessel segment in CFO acute incubation with tetrahydrobiopterin (BH4). *Significant difference between groups (P < 0.05; ANOVA followed by Duncan's test for multiple groups).