Quantitative Study of Brunner's Glands in the Human Duodenal Submucosa

Abstract

SUMMARY:The existence of Brunner's glands (BGs) in the duodenal submucosa is uncontestable, but their exact distribution along the full extent of the duodenal wall is unknown. Objective: To verify the BGs distribution along the human duodenum. Material and method: Twenty normal duodenums were examined. Two samples were removed from each of the four anatomical portions of the duodenum using a scalpel, in such a way that the whole circumference of each portion was excised. Sections were prepared and stained with hematoxylin-eosin. Twelve microscope fields were examined on each duodenal section. The mean numbers of glandular points per field were computed and compared, for the 12 microscope fields of each duodenal section examined. Results: The first duodenal portion presented large quantities of BGs in all of the fields examined. The second duodenal portion also showed the presence of BGs in all the fields examined, albeit in smaller quantities than in the first portion. In the third duodenal portion, BGs were present in six of the duodenums examined. In the fourth duodenal portion, there was a minimal quantity of glands, all located in only ten of the duodenums studied. Conclusions: BGs are present in the submucosa of all duodenal portions, with the greatest concentration in the first portion. Their concentration decreases significantly in the second portion of the duodenum. Furthermore, they become even fewer in number in the third portion and are minimally present in the fourth portion. 8 removed from 20 fresh adult cadavers, of both sexes, during the course of necropsies carried out in the Department of Pathology, School of Medical Sciences of Santa Casa de São Paulo. None of these cadavers presented any illness that might compromise the morphological integrity of the digestive system, as indicated through analysis of the clinical records and confirmed by the necropsy. After removal, each duodenum was immediately immersed in 10% formalin and taken to the Department of Morphology, where it was subsequently cut open and washed with running water. After complete inspection of the duodenal mucosa, which needed to be whole, small duodenal wall samples were removed with a scalpel (2 cm). The samples were obtained from each of the four anatomical portions of the duodenum (superior, descending, horizontal and ascending), in such a way that a segment encompassing the entire circumference of each duodenal portion was sampled. Each segment removed was then put back into 10% formalin, where it remained for 24 hours. The segments were then embedded in paraffin blocks. Following this, sections of five micrometers in thickness were cut and stained with hematoxylin-eosin. The BGs were analyzed quantitatively by means of the point counting technique, using a screen of 176 equidistant points, projected via a monitor showing the field to be quantified. Each sample was examined under 400x magnification. Twelve microscope fields were examined on every representative slide of each duodenal portion and underwent morphometric study t...