Nitric oxide synthase-positive cells are detectable in gastroduodenal biopsies of patients with dyspepsia: A preliminary report.

We explored the possibility of detecting nitric oxide synthase (NOS) in gas troduodenal biopsies of patients with functional dyspepsia. Biopsies were o btained from 10 patients (mean age 52.3 +/- 14.1 y, M:F = 1.5) during an oe sophago-gastro-duodenoscopy (OGD). They were fixed in 5% formalin, embedded in paraffin and stained immunocytochemically for neural NOS (bNOS). The ce lls were counted independently by two observers in four high power fields ( hpf) and averaged. The duodenum stained for bNOS-immunoreactivity in more p atients (n = 8) than either the corpus (n = 7) or the antrum (n = 3). The m ean total cell count in gastroduodenal biopsies was 11.6 +/- 10 cells per H PF. In addition to this, bNOS was detected in varicose as well as non-varic ose nerve fibres in the lamina propria mucosae. Parietal cells of the gastr ic corpus and duodenal epithelial cells also showed bNOS immunoreactivity. In conclusion, bNOS-positive cells are detectable in gastroduodenal biopsie s. This will facilitate in-depth study of the role of bNOS in patients with functional dyspepsia.