Mucosal Enzyme Activities, Peptide Hormone Concentrations and Hormone Secretory Granule Properties in Functioning Proximal Jejunum after Shunt Operation for Obesity

Abstract

Crosby capsule biopsies were obtained from functioning jejunum in 6 patients between 7 and 15 months after jejuno-ileal bypass for morbid obesity and compared with 6 normal control biopsies. Brush border and other mucosal enzyme activities and seven regulatory peptide concentrations were measured in each biopsy. Analytical subcellular fractionation by sucrose density gradient centrifugation was used to investigate brush border and peptide secretory granule properties. Specific activities of all the brush border enzymes assayed in the bypass patients were similar to the normal controls and subcellular fractionation studies showed no change in brush border properties. Similarly, properties of other mucosal organelles and their associated enzyme activities were unchanged in the bypass patients. The mucosal regulatory peptide concentrations in the bypass patients showed no significant difference from the normal controls and no changes were detected in peptide storage granule properties. These studies therefore support the concept that the adaptive changes occurring after jejuno-ileal bypass are due to changes in cell numbers or other parameters of function rather than changes in the specific activities of the brush border enzymes themselves. They also show that the marked abnormalities of plasma hormone release after bypass surgery are not in themselves due to alterations in mucosal hormone concentrations, or of the secretory granule properties.

Glucagon, Secretin and Vasoactive Intestinal Polypeptide Immunoreactivities in Rat Gut after Jejuno-Ileal Bypass and Resection

“…This contrast, together with the tendency for the non-func tional ileum to contain slightly more rather than less YY57 immunoreactivity, is not in dicative of a major hypertrophic or other role [3,7,16,35,37] for large glucagon precur sors) in the morphological changes which follow the operations. Dawson et al [7] re ported that the ileal enteroglucagon immuno reactivity was unchanged in the functional ileum of patients who had extensive JIB operations.…”

“…This contrast, together with the tendency for the non-func tional ileum to contain slightly more rather than less YY57 immunoreactivity, is not in dicative of a major hypertrophic or other role [3,7,16,35,37] for large glucagon precur sors) in the morphological changes which follow the operations. Dawson et al [7] re ported that the ileal enteroglucagon immuno reactivity was unchanged in the functional ileum of patients who had extensive JIB operations. Our results that ileum contains substantially more N-terminal-to-central im munoreactivity than other gut tissues in rats, agrees with those of Jacobs et al [16], These authors, however, reported that enterogluca gon levels in ileum and plasma of Wistar rats (180-230 g) were elevated by 60% following resection of the proximal two thirds of the small intestine and suggested a 'trophic role in producing intestinal growth'.…”

Comparative effect of distal and proximal intestinal resection and bypass on the rat exocrine pancreas

“…Intestinal resection provokes the hypersecretion of gastric acid, probably by increasing gastrin production [1,12,28]. Sorensen et al [20] and Dawson et al [5] found that bypass surgery has no important influence on the levels of gastrin produced. Junghanns et al [10] reported a less pronounced rise of serum gastrin levels after distal resection than after proximal resection (PR) in dogs.…”