Fig 2: Comparison of gastric NGF, GDNF, and TRPV1 expression in control and FD subgroups. (A) NGF expression in the EPS and mixed groups was higher than that in control (P = 0.017, P = 0.025). (B) GDNF expression in the PDS, EPS, and mixed groups was higher than in control (P = 0.009, P = 0.001, and P = 0.009, respectively). (C) TRPV1 expression was higher in the PDS, EPS, and mixed groups than in the control group (P = 0.037, P = 0.017, and P = 0.014, respectively). Comparisons were made by analysis of variance followed by Scheffe test. EPS = epigastric pain syndrome, FD = functional dyspepsia, GDNF = glial cell-line derived neurotrophic factor, NGF = nerve gsrowth factor, PDS = postprandial distress syndrome, TRPV1 = transient receptor potential vanilloid receptor 1.

Fig 3: Representative images of TRPV1 immunostaining of human gastric mucosa. TRPV1 staining of (A) H pylori-negative healthy control, (B) H pylori-positive healthy control, (C) H pylori-positive epigastric pain syndrome patient, and (D) H pylori-positive postprandial distress syndrome patient. (E) The same patient shown in (D), 1-year after H pylori eradication. Cytoplasms and cell junctions were stained (arrow) (×20 magnification). TRPV1 = transient receptor potential vanilloid receptor 1.