Figure 6. In humans, co-injection of β-alanine (ALA) and bovine adrenal medulla peptide 8–22 (BAM8-22) with or without histamine (HIS) does not change the areas of dysesthesia or skin reactions compared to the effects of one of the component pruritogens given alone.

(A) Areas of alloknesis, hyperalgesia, and hyperknesis and (B) areas of wheal and flare produced after injection of each pruritogen (BAM8-22, ALA), HIS, and combination of pruritogens. Data were analyzed with repeated measures ANOVA (RMANOVAs). Greenhouse–Geisser corrections were made for all analyses to correct for non-sphericity followed by Bonferroni post hoc tests (see main text and Supplementary file 2 for p-values). * indicates significant differences compared to HIS or BAM8-22 + ALA + HIS. Data from all subjects (n = 29) were included in the analysis. Data represent mean ± standard error of the mean (SEM).