Conservation of digestive enzymes.

@article{Rothman2002ConservationOD,
  title={Conservation of digestive enzymes.},
  author={Stephen S. Rothman and Charles Liebow and Lois Isenman},
  journal={Physiological reviews},
  year={2002},
  volume={82 1},
  pages={
          1-18
        }
}
The traditional understanding is that an entirely new complement of digestive enzymes is secreted by the pancreas into the small intestines with each meal. This is thought to be necessary because, like food itself, these enzymes are degraded during digestion. In this review we discuss experiments that bring this point of view into question. They suggest that digestive enzymes can be absorbed into blood, reaccumulated by the pancreas, and reutilized, instead of being reduced to their constituent… Expand
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  • 2015
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References

SHOWING 1-10 OF 178 REFERENCES
Enteropancreatic circulation of digestive enzymes.
TLDR
The pancreas appears to be able to recycle proteins much as the liver recycles bile salts, although the magnitude of this process remains uncertain. Expand
Enteropancreatic circulation of digestive enzyme as a conservation mechanism
TLDR
The experiments reported here are consistent with this latter view and suggest the circulation of approximately 60% of a mixture of digestive enzymes instilled into the duodenum (82–92% at steady state). Expand
Distribution and fate of pancreatic enzymes in small intestine of the rat.
TLDR
Diversion of pancreatic juice to the exterior of the body resulted in rapid disappearance of enzymes from the small intestine with virtually complete absence after 16 hr. Expand
Enteropancreatic circulation of digestive enzymes does not exist in the rat
The hypothesis of an enteropancreatic circulation1–3, that digestive enzymes are absorbed intact across the intestinal epithelium, are circulated through the bloodstream and rese-creted by the… Expand
The endocrine secretion of mammalian digestive enzymes by exocrine glands.
TLDR
A variety of evidence suggests that the endocrine secretion of digestive enzymes is a normal occurrence that can be of substantial magnitude in healthy individuals, is responsive to various physiological stimuli, and is distinct from exocrine secretion. Expand
Absorption of exogenous and endogenousproteolytic enzymes
TLDR
The method described does not seem to be useful as a pancreatic function test because it indicates absorption of the enzymes administered rather than release of secondary enzymes from the intestinal tract. Expand
Permeability of adolescent rat intestine to pancreatic ribonuclease.
TLDR
The experimental data favor simple diffusion of RNase across rat small bowel, but the amounts of pancreatic RNase absorbed were small, and while the data do not negate the concept of an enteropancreatic recirculation in the rat, only a minor quantity of luminal, pancreaticRNase could recirculate. Expand
The characterization of rat intestinal amylase.
TLDR
Pancreatic contamination of intestinal mucosa was extremely difficult to eliminate and pancreatic contamination must be carefully excluded as a source of enzymatic activity when studying intestinal enzymes. Expand
The physiology of secretin.
TLDR
The mucosal lining of the alimentary tube forms a number of hormones which regulate the motor and secretory activities of the organs of digestion, including secretin, which is the subject of this chapter. Expand
Effect of feeding on the protein synthesis in mammalian pancreas.
TLDR
It is concluded that continuous protein synthesis (at a constant rate) is a general feature of the mammalian pancreas under normal conditions. Expand
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