Concentration–response curves to ACh and CSE in precontracted arteries from female adult rats. Data show the effect in carotid (A,C) and iliac (B,D) artery segments with endothelium (+E, black symbols) and without endothelium (−E, white symbols). Relaxation is expressed as a percentage of maximal contraction to NA (10−7 M). Data represent the mean ± SEM; n indicates the number of segments from 4–5 different rats per group. Statistical analysis was performed by 2-way ANOVA, considering concentration and drugs (ACh or CSE) as factors. The p-value was extracted of the interaction term of the ANOVA. ACh, Acetylcholine; CSE, cocoa shell extract.