Some histophysiological aspects of Paneth’s cells of mice as shown by histochemical and radioautographical studies

Abstract

The histochemical study of proteins and polysaccharides revealed that Paneth''s cell granules of mice have 2 parts: a central protein and a peripheral carbohydrate, which resembles a capsule. In this way, it may be considered a sero-mucous cell. All reactive groups of proteins are well demonstrated in the granules; only the sulfhydril (SH) group was inconstantly demonstrated. The capsule is composed either of a combination of neutral and sulphate mucopolysaccharides or a sulpho-m weakly sulphated, orthochromatic and PAS [periodic acid Schiff]-positive. This capsule, which seems to be a protection against self-digestion, is pepsin and trypsin-fast. The granules showed maturation from Golgi''s zone towards the cell apex. This maturation is revealed by an increase of reactivity to protein methods and the appearance of the capsule which progressively increases in thickness. The younger capsules have either 1-2 glycol groups (PAS-positive) or sulphate groups (alcian blue positive), otherwise the eldest, i.e., the apical granules, have both groups and are PAS and alcian blue positive. The radioautographic study of cystine-S35 and tryptophan-H3 incorporation has shown that Paneth''s cell protein synthesis is like the protein synthesis of protein-secreting cells such as pancreatic acinar cells. Paneth''s cells are different from other epithelial cells of the crypts in that they are pre-goblet cells. Sulphate-S35 uptake revealed the presence of this radical in Paneth''s cell granules, probably associated with the mucin of their capsules, and also, proved the different behavior between this cell and the goblet cell, which has a predominant mucous secretion. The time of elaboration of granules, through estimation of the amino-acid uptake, was about 20-30 min. The same uptake showed that Paneth''s cells, although differentiating in mice on the 7th day, only begin their secretory activity between the 12th and 20th day of life, probably coinciding with weaning.