CHAP, ii EXTEKNAL DIGESTIVE SECEETIONS 



107 



The specific secretory organs of the stomach consist of two 

 kinds of glands, which differ both in the character of the cells that 

 line the duct and in the nature of their secretion. 



Most of the glands at the pyloric end have a long neck, lined 

 with cells identical with those on the surface of the mucosa, and 

 a short body, which is nearly always made up of a number of 

 tubules, lined with an epithelium that is quite different from that 

 of the neck or excretory duct. It consists 

 of finely granulated columnar cells, which 

 are never goblet-shaped, and which react 

 specifically to various stains (Fig. 35). In 

 the glands of the fundus the duct is 

 narrower, the neck shorter, and the body 

 longer. But they differ from the pyloric 

 glands mainly in having two kinds of 

 secreting cells: those which Heidenhain 

 termed chief the central or peptic cells, 

 and those he calls border the parietal or 

 oxyntic cells. The first are similar to the 

 cells of the pyloric glands, the second are 

 larger, more irregular in form, darker when 

 hardened in alcohol, more easily stained 

 (Fig. 36). It was formerly supposed, in- 

 correctly, that the first kind of glands were 

 found exclusively in the pyloric region, the 

 second in the curvature and fundus. In 

 reality the former are more abundant in 

 the pyloric and the latter in the fundic 

 region (Stohr). 



As we have seen for the salivary 

 glands, so in the gastric, the duct which 

 runs through the tubule is prolonged into 

 canaliculi between the cells, and forms a 

 basket-like capillary network round the 

 parietal cells (Fig. 37). 



The stomach is richly supplied with 

 blood by numerous vessels from the caeliac 

 trunk, which form a plexus beneath the submucosa. Each tubule 

 is lined with a capillary network, from which the veins form again. 

 They are few in number, but are larger than the arteries, with a 

 stronger muscular coat than is usual in veins, and many valves 

 (Hochstetter). 



The lymphatics of the stomach arise in a rete of lacunar spaces 

 that lie between the tubules of the gland and form a more ample 

 plexus in the submucosa, whence the efferent lymphatics emerge 

 to traverse the muscular coats and the lymph nodules situated 

 along the two gastric curvatures. 



FIG. 37. Secreting duct of gastric 

 gland. Golgi's silver chromate 

 method. (E. Miiller..) Thecells 

 are not represented, but the 

 lumen extending into the net- 

 work surrounding the parietal 

 cells is deeply stained. 



