Changes in microvascular structure of the fibrotic pancreas and their influence on pancreatic endocrine function.

The objectives of this study were to clarify the microvascular structure in and around the Langerhans' islands of the normal pancreas, elucidate how the structure changes with advance of pancreatic fibrosis owing to stagnation of pancreatic juice, and how these changes influence the endocrine function of the pancreas. For these purposes, the changes in microvascular structure of the fibrotic pancreas, produced by ligation of the pancreatic duct in mongrel adult dogs, were investigated by microangiography and injection replica scanning electron microscopic methods. In addition, the endocrine function of the pancreas was studied by the intravenous (iv) glucose tolerance test. The results revealed that the basic blood vessel structure of the Langerhans' islands, and its insulin secretory function, were maintained relatively well in the long-term, duct-ligated pancreas though the capillary network spreading in the pancreatic exocrine part could hardly be observed.