Henry Gray (18251861). Anatomy of the Human Body. 1918.
open into a single duct. The duct, however, in these glands is shorter than in the pyloric variety, sometimes not amounting to more than one-sixth of the whole length of the gland; it is lined throughout by columnar epithelium. The gland tubes are straight and parallel to each other. At the point where they open into the duct, which is termed the neck, the epithelium alters, and consists of short columnar or polyhedral, granular cells, which almost fill the tube, so that the lumen becomes suddenly constricted and is continued down as a very fine channel. They are known as the chief or central cells of the glands. Between these cells and the basement membrane, larger oval cells, which stain deeply with eosin, are found; these cells are studded throughout the tube at intervals, giving it a beaded or varicose appearance. These are known as the parietal or oxyntic cells, and they are connected with the lumen by fine channels which run into their substance. Between the glands the mucous membrane consists of a connective-tissue frame-work, with lymphoid tissue. In places, this later tissue, especially in early life, is collected into little masses, which to a certain extent resemble the solitary nodules of the intestine, and are termed the lenticular glands of the stomach. They are not, however, so distinctly circumscribed as the solitary nodules. Beneath the mucous membrane, and between it and the submucous coat, is a thin stratum of involuntary muscular fiber (muscularis mucosæ), which in some parts consists only of a single longitudinal layer; in others of two layers, an inner circular and an outer longitudinal.
FIG. 1054 A pyloric gland, from a section of the dogs stomach. (Ebstein.) m. Mouth. n. Neck. tr. A deep portion of a tubule cut transversely. (See enlarged image)
Vessels and Nerves.The arteries supplying the stomach are: the left gastric, the right gastric and right gastroepiploic branches of the hepatic, and the left gastroepiploic and short gastric branches of the lienal. They supply the muscular coat, ramify in the submucous coat, and are finally distributed to the mucous membrane. The arrangement of the vessels in the mucous membrane is somewhat peculiar. The arteries break up at the base of the gastric tubules into a plexus of fine capillaries which run upward between the tubules, anastomosing with each other, and ending in a plexus of larger capillaries, which surround the mouths of the tubes, and also form hexagonal meshes around the ducts. From these the veins arise, and pursue a straight course downward, between the tubules, to the submucous tissue; they end either in the lienal and superior mesenteric veins, or directly in the portal vein. The lymphatics are numerous: they consist of a superficial and a deep set, and pass to the lymph glands found along the two curvatures of the organ (page 706). The nerves are the terminal branches of the right and left