Behaviour of digestive enzymes in the pancreatic juice and pancreas of rats fed on a low-protein diet (3 p. 100 of cereal protein) then on a balanced diet (23.5 p. 100 of mixed protein).

The aim of this study in the rat was to determine the effect of a low-protein diet (3 p. 100 cereal protein) and balanced refeeding (23.5 p. 100 mixed protein) on the activity of some pancreatic digestive enzymes and the amount of their secretion. Parallel studies were carried out on the pancreas and its exocrine secretion. 1) With a low-protein diet (21 days), there was a decrease in the amounts of bile and pancreatic juice secreted. During balanced refeeding (18 days), the amount of bile secreted returned to normal and, although that of the juice increased, it was less than the amount secreted by the reference lot. 2) Body and pancreatic weights decreased slightly with the low-protein diet. The protein content and mitotic ability of the pancreas declined. However, during balanced refeeding, the ponderal weight of the pancreas returned to normal more rapidly than that of the overall organism. Pancreatic protein content and mitotic ability also augmented. 3) The low-protein diet produced an overall decrease in enzyme activity in the pancreas and in the juice. However, in the absence of any dietary stimulation, these activities were not affected proportionally in the same way as the pancreas and its exocrine secretion. Nevertheless, no disturbance in the digestion and absorption of the ration was observed. 4) During balanced refeeding, enzyme activities increased to different levels in the juice and the pancreas but after 18 days total enzyme activity had not been entirely recovered. 5) Enzyme activity varied widely, especially during the first 48 hrs of malnutrition and the first 36 hrs of refeeding.