Thyroid C-cells have the capacity to produce a variety of peptides, as do C-cell tumors. The cellular content of one such peptide, somatostatin, is restricted to a minority of C-cells in rat and human. We set out to clarify whether the synthesis of somatostatin is equally restricted and to study changes that occur in somatostatin synthesis with age. We used immunocytochemistry to localize somatostatin and calcitonin in conjunction with in situ hybridization, using digoxigeninlabeled oligoprobes to localize somatostatin and calcitonon calcitonin, and somatostatin synthesis, as shown by mRNA content, is limited to the subset of cells containing immunoreactive somatostatin. The numbem of C-cells in general and of the subset synthesizing somatostatin increase between juvenile and adult animals, but the somatostatin cells remain confined to a small area of the gland. These findings support the proposal that somatostatin production is not facultative, but that C-cells differentiate into two distinct sub-
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We have studied a series of 22 human medullary carcinomas (MCTs), both primary and metastatic, using immunocytochemistry (ICC) to localize calcitonin and somatostatin peptide and in situ hybridization (ISH) to localize calcitonin and somatostatin mRNA. All tumors were positive for calcitonin peptide with ICC, which often showed considerable intercellular heterogeneity, with many cells having undetectable levels of calcitonin. However, calcitonin mRNA localized by ISH was much more uniformly distributed, indicating that MCT tumor cells may retain the capacity to both synthesize and store calcitonin, whereas others lose their storage but not their synthetic capacity. Somatostatin peptide and mRNA were found in tumors from 15 patients. In contrast to the pattern seen with calcitonin, somatostatin mRNA and peptide were usually found in single scattered cells. When correlation was possible, the same cell showed positivity for somatostatin mRNA on ISH and positivity for somatostatin peptide on ICC. However, in one tumor many more cells were positive for mRNA than for peptide, suggesting that only a proportion of cells retained the ability to store the peptide. The variation in cellular content of immunoreactive calcitonin is interpreted as resulting from either an increased tumor growth rate or reduced ability to store peptide in a less differentiated tumor. With somatostatin there was good correlation between mRNA and peptide content, but it occurred in single widely scattered cells, most tumor cells being negative for both peptide and mRNA. It is suggested that somatostatin production might be associated with a reduction in the growth of the cell concerned, either through a differentiation step or through a direct effect of the hormone.(ABSTRACT TRUNCATED AT 250 WORDS)
Twelve patients, who previously had surgery for peptic ulcer, underwent a Roux-en-Y procedure for the treatment of a combination of severe symptoms. The original operation was truncal vagotomy with pyloroplasty in 7 and Billroth II gastrectomy in 5 patients. In those 5 patients a truncal vagotomy was added. Enterogastric reflux (EGR) was documented preoperatively with milk-EHIDA scintigraphy in all of them, and 8 patients had dumping syndrome with a positive dumping provocation test (DPT). Recurrence of ulceration was found preoperatively in 4 patients. All patients were classified as Visick III or IV. At an average follow-up of 2.5 years, all patients but 1 were classified as Visick I or II. DPT was negative and EGR was almost totally abolished in all subjects. Only 3 patients had mild symptoms of gastric stasis, although gastric emptying of solids as evaluated with gastric scintigraphy of a labelled test meal was found significantly delayed in all patients as compared to healthy volunteers. Gastrectomy with Roux-en-Y gastrojejunostomy is an effective procedure for the treatment of enterogastric reflux, dumping syndrome and recurrent ulceration, especially when these problems coexist in the same patient.
Fourteen guinea pigs were given prednisolone daily for 20 days and 11 for 40 days. Another 20 formed the two control groups. Short-term prednisolone treatment significantly increased serum gastrin levels and antral G-cell population as compared to the control group. The same parameters significantly decreased following 40 days of prednisolone treatment as compared to the group of short-term prednisolone treatment. Forty days of prednisolone treatment significantly increased antral D-cell population as compared to the control and short-term prednisolone treatment groups. It is concluded that hypergastrinaemia and antral G-cell hyperplasia following corticosteroid administration is temporary and is accompanied by antral D-cell hyperplasia.
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