Patterns of blood supply to the gastric mucosa. A comparative study revealing an end-artery model.

The form of the gastric arterial supply to the mucosa has been studied in dog, swine, ferret, cat, guinea-pig, rabbit and rhesus monkey. In all these species, the bore of vessels in the submucous plexus diminished from body to pylorus, though this was most marked in the guinea-pig and rabbit. The plexus was also continuous across the pylorus with duodenal vessels. Thus the well known poverty of vascularity in distal parts of the human stomach is shared by other species and is unlikely to be a contributory factor to the initiation of peptic ulcer, a disease limited to man. In dog, swine, ferret and cat, as in man, the primary (largest) and secondary (smaller) components of the plexus lay entirely in the submucosa. In the cat, there was a secondary plexus of much smaller vessels deep to the muscularis mucosae. In the guinea-pig, rat, rabbit and monkey, both plexuses were mostly embedded within the muscularis mucosae. As a result, mucosal arteries had two modes of origin: (a) the first, in which they did not pass through the muscularis mucosae as exemplified in the cat, and (b) the second, where they did pass through muscularis mucosae as exemplified by the dog, ferret and swine; in other species, they passed through part of the muscularis mucosae. Areas of mucosa supplied by a single mucosal artery were measured, and ranged widely from the smallest in the cat to the largest in the dog. These features do not seem to have been reported previously, and may be associated with as yet undiscovered functional mechanisms of the muscularis mucosae. Mucosal arteries of extramural origin were found to occur occasionally in the guinea-pig and rabbit, and hence these may provide an experimental model of the pattern existing in man.