Masafumi Hara

Immunohistochemical studies of endocrine cells in heterotopic pancreas

Twenty-one specimens of heterotopic pancreas were investigated using the indirect immunoperoxidase method for insulin, somatostatin, glucagon, pancreatic polypeptide (PP) and gastrin. Ten specimens showed ducts, acini and islets, seven showed ducts and acini, and four showed a ductal component alone. Pyloric gland-like mucous glands were occasionally identified in association with the ductal component. In eight of ten lesions containing islets, the islets were round and had a clearly defined outline with many glucagon cells and either none or a modest number of PP cells (dorsal type). In the remaining two lesions, the islets showed varying sizes and irregular outline with many PP cells and a few or no glucagon cells (ventral type). In either type of islets, insulin and somatostatin were detected, but gastrin cells were absent. Some isolated endocrine cells were also present among the acinar and ductal components. Their occurrence in ducts was more frequent in lesions or areas mainly composed of the ductal compoment than in those with less prominent ductal tissue. In eight lesions a few gastrin cells were found in the ductal component which showed goblet cell metaplasia and pyloric gland metaplasia. An intimate relationship between goblet cell metaplasia and appearance of G cells is noteworthy.

GASTRIC METAPLASIA IN DUODENAL ULCER. Histochemical Considerations of Its Pathophysiological Significance

Gastric metaplasia of the duodenal mucosa in biopsy specimens of healed duodenal ulcer and in surgical specimens of perforated duodenal ulcer was investigated using mucin histochemistry and the indirect immunoperoxidase method. Endoscopic methylene blue test was performed prior to biopsy. All specimens from areas showing no dye absorption revealed varying degrees of gastric metaplasia characterized by heterotopic occurrence of gastric‐type foveolar cells mainly at the tips of stunted intestinal villi. On average, 31.8% of the total surface length of duodenal mucosa taken from areas showing no dye absorption was occupied by the metaplastic cells. They showed strong reactivities for periodic acid‐Schiff (PAS) and galactose oxidase‐Schiff sequences, while alcian blue and paradoxical concanavalin A staining, class III, were negative. Immunoperoxidase‐PAS double staining revealed a few gastrin and somatostatin cells in foci of gastric metaplasia, but almost no cells containing motilin, secretin, cholecystokinin and gastric inhibitory peptide. Such endocrine cells were scattered in nonmetaplastic mucosa. While such metaplastic change has been regarded as a self‐defence mechanism or adaptation of the duodenal mucosa against acid, a local decrease of normal endocrine cells, which allegedly function as acid receptors, may lead to alterations of gastroduodenal interaction. It is suggested that gastric metaplasia is important as one of the pathophysiological mechanisms involved in the recurrence of duodenal ulcer. ACTA PATHOL JPN 38 : 1011 ∼ 1018, 1988.

Application of parietal cell autoantibody to histopathological studies.

Parietal cell antibody (PCA) from the serum of a patient with type A gastritis was used for the immunohistochemical demonstration of human parietal cells not only in frozen sections but in paraffin‐embedded biopsy specimens. The antigenicity was occasionally lost in paraffin sections of routine surgical materials. With the indirect immunoperoxidase technique, PCA clearly detected antigenic substances on the intracytoplasmic canalicular structures and focally on the apical plasma membranes. These intracellular localization patterns differed from those of intrinsic factor, which was present on fine vesicular structures along the intracytoplasmic canaliculi and apical plasma membranes. A few PCA‐reactive cells were further demonstrated in normal pyloric glands, atrophic fundic glands with pseudopyloric gland metaplasia and cystic changes, a hamartomatous polyp in the fundic mucosa, and in heterotopic gastric mucosa in the duodenum. Developing parietal cells in the newborn stomach were also visualized by PCA. In one of 16 surgical specimens of gastric cancer, abortive gland lumens formed by the cancer cells were focally positive with PCA. Immunostaining with PCA was, therefore, a useful tool for the detection of pathological alterations of human parietal cells in routine histopathology specimens. ACTA PATHOL. JPN. 35: 823–829, 1985.

SOLITARY GASTRIC POLYPS IN THE FUNDIC GLAND AREA A Histochemical Study

Six solitary gastric polyps in the acid‐secreting fundic mucosa were histo‐chemically investigated using the mucin histochemistry, immunoperoxidase method, and silver methods for endocrine cells. Histologically, the polyps were grouped into three types : they largely consisted of either hyperplastic foveolar cells (group 1), normal‐appearing fundic gland cells with mild cystic changes (group 2) or hyperplastic fundic gland cells with cystic dilatation (group 3). The presence of parietal cells and mucous neck cells was confirmed in all polyps by the immunoperoxidase method using parietal cell autoantibody and the paradoxical Concanavalin A staining, respectively. Regarding the endocrine component, somatostatin‐containing cells, Grimelius‐positive argyrophil cells, and Fontana‐Masson‐positive enterochromaffin cells were scattered in the fundic gland area of the polyps as well as in the surrounding normal‐appearing fundic mucosa. Gastrin‐containing cells were absent. In one of the group 2 polyps and both group 3 polyps, a varying number of glicentin‐containing cells were found among the fundic gland components : In one polyp in group 3, glucagon immunoreactivity was detected in the glicentin‐containing cells. These findings suggest that some of the polyps express characteristics of the fetal fundic mucosa, since glicentin and glucagon immunoreactivities in normal human stomach have been detected exclusively in the fetal fundus. ACTA PATHOL. JPN. 35: 831–840, 1985.

Studies on the Phenomenon of Locational Variation in the Speed of Discoloration During the Endoscopic Congo Red Test. The First Report: Quantitative Study of Parietal Cell Populations by Cell Isolation Method

A quantitative study of parietal cell populations was done using the cell isolation method designed by the authors in order to investigate the cause of the phenomenon of locational variation in the speed of discoloration during the endoscopic Congo red test. The endoscopic Congo red test was performed in three mongrel dogs and five patients with peptic ulcers. In each case, at the time when spotty discoloration was observed, three biopsy specimens were obtained from both the quickly discolored portion (Q) and the slowly discolored portion (S) of the greater curvature of the middle body. After determination of wet weight, the biopsy specimens, having been separated into two groups (the Q‐group and the S‐group), were digested simultaneously with collagenase and dispose in the same way in each case. The number of parietal cells per microlitre in the obtained cell suspensions were counted using Neubauers hemocytometer, staining with tetranitroblue tetrazolium. The number of parietal cells per milligram tissue wet weight was calculated for each sample from both groups. The number of parietal cells per milligram wet weight of the quickly discolored portion was 2.0 times (on average) as large as that of the slowly discolored portion in the case of the dogs. In the case of patients, the former was 1.7 times (on average) as large as the latter, with a statistically significant difference. We concluded that the locational variation of the speed of discoloration during the endoscopic Congo red test may be mainly due to the unequal distribution of parietal cells.