COMPARATIVE HISTOCHEMISTRY OF THE GASTRIC MUCOSA: A SURVEY OF THE COMMON LABORATORY ANIMALS AND MAN.

A comparative histological and histochemical study of the gastric mucosa was done with the frog, mouse, rat, hamster, guinea pig, rabbit, cat, dog and man. Enzymatic histochemical studies were done to demonstrate acid phosphatase (PbS and azo-dye methods), thiamine pyrophosphatase (TPP-ase) and NADH2 tetrazolium reductase activity. Cytoplasmic organelles were stained in some cases by three of the above methods i.e. acid phosphatase (PbS) activity marked the lysosomes, TPP-ase activity marked the Golgi apparatus and NADH2 tetrazolium reductase activity marked the mitochondria. The acid phosphatase activity of the four major cell types was markedly different in the various species. The activity shown by both methods in individuals of a given species coincided well except in the rabbit and the dog. TPP-ase activity demonstrated the Golgi region in the surface cells of all species except the guinea pig and the frog. The Golgi zones of zymogen cells showed strong activity only in the cat, while the parietal cell Golgi was not demonstrated in any of the species. NADH2 tetrazolium reductase activity in the parietal cells was strong in all animals except the mouse and the rat where staining was faint. The relationship between the lysosomes and the Golgi apparatus, as demonstrated histochemically in the gastric cells of the nine species, is discussed. The functional significance of these different enzymatic patterns has yet to be determined.