Altered tryptophan hydroxylase 2 expression in enteric serotonergic nerves in Hirschsprung’s-associated enterocolitis

Figure 3 Double-labelled immunofluorescence. Series (A) to (D) demonstrate the incremental reduction in tryptophan hydroxylase-2 immuno-positive cells in the myenteric plexus from healthy control, to ganglionic bowel in HSCR through to aganglionic bowel. The bar graph in (E) demonstrates the mean cell counts of TPH2 immuno-positive cells, with a reduction seen particularly in transition zone and aganglionic bowel, and slight variation seen in the ganglionic bowel of those with pre-operative HAEC vs those who did not. TPH2: Tryptophan hydroxylase-2; HSCR: Hirschsprung’s disease; HAEC: Hirschsprung’s-associated enterocolitis.