Morphological changes after duct ligation of rabbit pancreas.

The morphological changes in rabbit pancreases after duct ligation were studied. These changes do not occur synchronically within the whole pancreas. The most advanced are those in the head portion; in the tail, their development is delayed. Pancreas duct ligation results in the pancreas edema, a gradual disappearance of zymogenous cells, replacement of acini by small ducts, an occasional differentiation of new zymogenous cells that quickly extinct again, and with the occurrence of amorphous or even fibrillary masses in the cytoplasm of duct cells to their further reduction. These changes are accompanied by the formation of loose connective tissue which gradually fibrotizes. The islets of Langerhans also undergo changes. In the tubules, a differentiation appears of their cells into endocrine elements. The existing islets get destroyed by both the fibrotic tissue and the formation of cavities in large islets with a consequent break-up of those islets. Both these destructive processes, in connection with the new formation, result in the appearance of small islets on the surface of which there is a capillary network. The cells of those islets are not of a fetal character.