Rapid Adaptation of Pancreatic Enzyme Secretion in the Conscious Rat

Abstract

The influence of fasting and dietary modulation on basal and stimulated pancreatic enzyme secretion was studied in conscious rats with cannulated pancreatic ducts. Two days’ fasting decreased pancreatic secretion by about 30%. After stimulation of the secretion rate by acute derivation of pancreatic juice or by intravenous infusion of cerulein (0.2 µg/kg/h) no rapid change of enzyme composition was found. In further experiments, two groups of rats were fed with carbohydrate-rich and carbohydrate-poor diets, respectively. After pancreatic duct cannulation and a postsurgical recovery period, the diets were interchanged. An adaptation of pancreatic enzyme secretion to the new diet was observed in pancreatic juice. Stimulation of the secretion rate during the adaptation process by acute derivation of the juice or by intravenous infusion of either cerulein, secretin, carbachol or cerulein plus secretin did not further modify the composition of pancreatic proteins. ‘Nonparallel secretion of enzymes was never found when sufficient time for recovery from pancreatic duct surgery was allowed.

Absence of Rapid Adaptation of the Exocrine Pancreas of Conscious Dogs to Diets Enriched in Fat or Carbohydrates

“…Finally, our results about the absence of rapid adaptation are in agreement with those reported by Keim (1986) working with an experimental model that allows the measurement of basal and stimulated pancreatic secretion in conscious rats.…”

Effects of diets containing casein and rapeseed on enzyme secretion from the exocrine pancreas in the pig

“…Each enzyme behaves differently, depending on the amount and the type of substrate ingested. In rat (Keim, 1986), pig (Corring, 1979) or man (Bucko et al 1982), trypsin (EC 3.4.21 .4) and chymotrypsin (EC 3.4.21.1) activities increase with a protein-rich diet, chymotrypsin being more sensitive to this dietary modulation. Giorgi et at.…”