Autoradiographic Observations on the Mucous Cells of the Stomach and Intestine

Abstract

MuciNs are produced from three morphologically distinct types of cell in the mammalian stomach, viz. the superficial epithelium which forms a continuous covering, the mucoid neck cells of the fundal glands, and the pyloric glands. Possibly the cardiac glands, which consist of mucus-producing cells, and are a conspicuous feature in some species, represent a fourth type of mucous cell.The duodenal or Brunner's glands are composed of mucous cells, although in some species, for instance the rabbit and horse, "serous" cells are present in addition.Goblet cells, which produce mucin, are found throughout the small and large intestines. In the small intestine they occur both in the crypts of Lieberkuhn and on the villi. The colon contains large numbers, most closely packed in the crypts but also scattered among the surface epithelium. They are relatively scarce in the csecum of the rabbit and guinea-pig, where they are found principally at the bases of the shallow crypts.Some of the mucins secreted by these various cells contain sulphur, probably in the form of ester sulphate groups. The present experiments have been concerned with observations on the incorporation and excretion of 35S, administered intravenously either as Na235SO4 or as [35S] methionine, by the various types of mucous cell. EXPERIMENTALComparative observations were made on mice, rats, guinea-pigs, rabbits and cats. Material was obtained from 6 mice, killed 1, 21, 3, 6, 12 and 24 hrs. respectively after the injection of radioactive sodium sulphate; from 9 rats killed 1 hr. 10 min., 2 hrs. (2 animals), 3 hrs. (4 animals) and 24 hrs. (2 animals) after sulphate; from 3 rabbits killed at 21, 61 and 24 hrs.; 2 guinea-pigs killed at 2 and 61 hrs.; and 2 cats killed at 21 and 6 hrs. after sulphate.Two of the mice (killed at 1 and 21 hrs.) and two of the rats (killed at 2 and 24 hrs.) had dilute mustard oil inserted into a loop of the colon for 4 hours to empty and stimulate the goblet cells, as previously described [Jennings and Florey, 1954]; the oil was removed immediately before sulphate was given.131

Demonstrations

“…After dialysis bound radioactivity, expressed as counts/min per min of secretion, increased with time and reached a plateau between 2 and 4 hr. This agrees with Jennings & Florey (1956), where mucus epithelial cells maximally incorporated 35SO42-within 1 hr and retained it for 3-6 hr.…”

Radioimmunoassay of human intestinal goblet cell mucin. Investigation of mucus from different organs and species.

“…A heavy reliance has l)een place(d upon labeling with radioactive precuirsors (6)(7)(8)(9), but these precursors are also incorporated into noninucin-glycoproteinis, often inore actively thanl into mucinis (10). As a result, one cannot be certain that contaminiation of mucin preparationsi by sismall amotunts of nonimiucin glycoproteins mlight not account for miuch of the radioactive inicoporatioin dlatat.…”

A histochemical study of human alimentary tract mucosubstances in health and disease. I. Normal and tumours.

“…Spicer, 1960Spicer, , 1962, little is known about the character and chemical composition or the cell of origin of the mucosubstances of different parts of the human alimentary tract under normal conditions and in various pathological conditions.The lack of the histochemical specificity of the early empirical stains made it difficult to reach any conclusions other than that there are several different kinds of mucosubstances as shown by differences in the staining properties, even of the same type of cell, in different species (Jennings and Florey, 1956).With the development of new histochemical methods, specific for different chemical components of mucosubstances, correlation between autoradiographic, histological staining reactions and chemical information available permitted better and rather thorough characterisation of alimentary tract mucosubstances of many animals. On the other hand, there have been few studies of human alimentary tract mucosubstances (Lev, 1966, and Lev andSpicer, 1965), whether normal or pathological, and the relationship between histochemical, chemical and autoradiographic results is still not revealed.…”

“…The lack of the histochemical specificity of the early empirical stains made it difficult to reach any conclusions other than that there are several different kinds of mucosubstances as shown by differences in the staining properties, even of the same type of cell, in different species (Jennings and Florey, 1956).…”