THE STRUCTURE OF THE GLANDS OF BRUNNEB 



IF. THE GLANDS OF BRUNNER OP DIDELPHYS VIRGINIANA 



The glands of Brunner in the opossum form a narrow ring around the pyloric 

 orifice of the stomach. In a preparation of the stomach and duodenum, cut open 

 along the line of attachment of the hepatogastric and hepatoduodenal ligaments, one 

 may see in the mucous membrane at the gastro-diiodcnal junction with a low magnifica- 

 tion, a number of minute funnel-shaped depressions, forming two or three irregular 

 rows more or less parallel with the line of junction of the stomach and intestine, and 

 at distances of two to three millimeters apart. On examination in sections these prove 

 to be the openings of tubular depressions of the mucous membrane into which 

 the glands of Brunner open. These depressions are not, however, in the strict sense, 

 the ducts of the glands, but rather evaginations of the mucous membrane as a whole, 

 because, in the inner portions of them, villi project from the wall into the cavity, and 

 small intestinal glands occur, beneath which a continuation of the longitudinal fibers 

 of the lamina muscularis mucosse may be seen. These intestinal elements may be 

 traced to a short distance below the level of the lamina muscularis mucosse of the 

 stomach and intestine, where the depression opens into a cavity of considerable size, 

 around which the lobules of the glands of Brunner are clustered, and into which the 

 ducts of the latter open. If the stomach and intestine, and after ligation of the latter 

 some inches below the pylorus, be distended with the fixing fluid, under sufficient pres- 

 sure to overcome the resistance of the pyloric sphincter and to dilate the opening to a 

 width of about 1.5 cm., one sees at the gastro-duodenal junction, instead of the depres- 

 sion referred to above, a number of rounded patches which are smooth and devoid of 

 villi. In sections of such a preparation, the appearance represented in Plate XIX, 

 Fig. 1 is observed ; the lobules of the glands of Brunner are clustered around a place 

 where the ordinary elements of the intestinal mucous membrane are lacking and only 

 an epithelium is to be seen. Through large openings in this epithelium empty the 

 ducts of the glands of Brunner. The first row of these defects in the intestinal mucous 

 membrane occurs at or near the gastro-duodenal junction, that is to say, the first row 

 of patches into which the glands of Brunner open may be continuous with the mucous 

 membrane of the stomach, or may be separated from the latter by a minute interval, 

 about O.lmm. in width, in which villi, intestinal glands, etc., may be found. In the 

 former case, the glands of Brunner have the appearance of being a continuation of the 

 pyloric glands; in the latter, they appear to be entirely separated from them. 



The extent of the glands of Brunner in a longitudinal direction is about 6.7 mm., 

 beginning about 1.2 mm. above the point where the gastric and duodenal epithelium 

 meet, and extending a distance of 5mm. to 5.5mm. into the tela submucosa of the 

 duodenum. They form a series of angular lobules, some entirely separate, others 

 aggregated into larger or smaller lobes. 



The glands are of a branched acinotubular type. The smaller lobules have as a 

 rule a single tubular duct which opens on the surface of one of the depressions above 



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