Adaptation of the Activities of the Brush Border Hydrolases along the Small Intestine of the Rabbit after Pancreatic Duct Ligation

Abstract

The activities of the brush border hydrolases (disaccharidases, α-amylase, γ-amylase, alkaline phosphatase, and aminopeptidases) were determined 2, 6, and 10 weeks after pancreatic duct ligation at 12 different levels of the digestive tract of the rabbit. The activities depended on the nature of the enzyme, on the time elapsed after the ligation, and on the intestinal segment considered. Maltase and γ-amylase activities increased as early as the second week, mainly in the jejunum. Sucrase, trehalase, α-amylase, alkaline phosphatase, and aminopeptidase activities, after a temporary decrease, significantly rose, only from the 10th week on, in an identical manner both in the ileum and the jejunum.

Rapid Adaptation of Pancreatic Enzyme Secretion in the Conscious Rat

“…It is well known that pancreatic secretion is considerably redundant in that only after reduction to less than 10% of nor mal a significant impairment of digestive function can be found [5], 90% reduction of pancreatic exocrine tissue does not lead to a reduced weight gain compared to sham-oper ated control animals [2], After induction of nearly complete atrophy of the exocrine pan creas by intraductal injection of oleic acid, remnant pancreatic tissue compensates by in creased basal and stimulated secretion rate [15]. Furthermore, an impaired pancreatic secretion rate is known to be accompanied by adaptive changes in the gut [3,7,17]. It is therefore unlikely that normal digestive func tion depends significantly on acute adapta tion of pancreatic secretory proteins to a sin gle meal manifested by nonparallel secre tion.…”