The Study of the Mechanism of Synthesis and Excretion of Amylase in Pancreas

Abstract

The Pancreozymin-Secretin test seems to have some limitation for the diagnostic evaluation of the pancreatic exocrine function. Some basic experiments were performed to investigate the reaction mechanism of pancreatic cells to pancreozymin stimulation.
1) Pancreozymin stimulates and increases the secretion of amylase in rat pancreas slices.
2) 30 minutes are needed until the newly synthesized enzyme is transported and excreted from the cells with pancreatic stimulation.
3) The effect of pancreozymin on exocrine cells seems to accelerate the first step of the transportation of the newly synthesized ribosomal enzymes to the menbrane system.
4) The synthesis of RNA and of protein by pancreatic cells is stimulated by pancreozymin in vitro.
5) Amylase secretion is still stimulated by pancreozymin when synthesis of RNA or of protein is inhibitted. The activity of ATPase and of alkaline phosphatase in the cells is increased by pancreozymin, and the turnover rate of phospholipid fraction of the cell is stimulated by pancreozymin. From these results, it seems that the increase of enzyme secretion is initiated through the energy metabolism in the cell, but not through the stimulation of protein synthesis.
6) Both theophyllin and dibutyryl 3'5' cyclic AMP stimulate the secretion of amylase in rat pancreas slices. And they stimulate the transport of the newly synthesized ribosomal enzyme to the membrane system like pancreozymin.
7) Both theophyllin and dibutyryl 3'5' cyclic AMP do not stimulate the synthesis of the protein in vitro.
8) Perhaps there may be some differences in mechanisms between the energy metabolism by pancreozymin and by cyclic AMP.