Long-term effect of growth promoting conditions on the exocrine pancreas of rats

Pancreatic adaptation following prolonged exposition to growth promoting conditions (protease inhibitor feeding, B II subtotal gastrectomy, subtotal colectomy) was studied in rats. Fifty male Wistar rats were divided into 5 groups: controls (n = 10), sham-operated (n = 10), low dose protease inhibitor feeding (n = 10), B II subtotal gastrectomy (n = 10), and subtotal colectomy (n = 10). After 4 mo a significant increase in pancreatic wet wt and DNA content was observed in rats after protease inhibitor feeding (p < 0.01), B II gastrectomy (p < 0.01), and subtotal colectomy (p < 0.05). Pancreatic total protein and lipase content were significantly increased in these three groups. Amylase and trypsin content increased after feeding the protease inhibitor (p < 0.01) and following B II subtotal resection (p < 0.01) but were unaffected after subtotal colectomy. Comparing the long-term effects (4 mo) with our previously published short-term data (4 wk) under the same experimental conditions, pancreatic trophism after 4 mo is less pronounced but characterized by a change in the enzyme composition with an increase in pancreatic lipase content.