AJP - Gastrointestinal and Liver Physiology, Vol 247, Issue 6 611-G616, Copyright © 1984 by American Physiological Society
Two distinct adaptive responses in the synthesis of exocrine pancreatic enzymes to inverse changes in protein and carbohydrate in the diet
J. Schick, R. Verspohl, H. Kern and G. Scheele
Rates of synthesis of 16 individual pancreatic exocrine proteins; tissue
concentrations of amylase, trypsinogen, and chymotrypsinogen; and
morphological assessment of pancreatic acinar cells were studied in the
exocrine pancreas in response to inverse changes in protein and
carbohydrate in the diet, administered for 12 days. Two distinct patterns
of response were observed. During adaptation to diets containing normal
protein (22%) or increased levels of protein (30, 45, 64, and 82% protein)
and correspondingly decreased levels of carbohydrate, amylase and the
majority of protease zymogens were synthesized in direct proportion to the
nutritional substrates carbohydrate and protein, respectively, in the diet.
With increases in dietary protein, anticoordinate patterns of response in
the synthesis of exocrine isoenzymes were observed: 0.4- to 2.0-fold
increases in trypsinogen forms 1 and 2, chymotrypsinogen forms 1 and 2,
proelastase 1, and procarboxypeptidases A and B; 5- to 7-fold decreases in
amylase forms 1 and 2; and insignificant changes in trypsinogen 3,
proelastase 2, lipase, and ribonuclease. During adaptation to diets
containing normal protein (22%) or decreased levels of protein (0 or 10%
protein) and correspondingly increased levels of carbohydrate, amylase and
the majority of protease zymogens were synthesized in inverse proportion to
nutritional substrates in the diet.(ABSTRACT TRUNCATED AT 250 WORDS)
