Involution of the pancreas after ligation of the pancreatic ducts. I: a histological study.

A detailed histological study of pancreatic involution after ligation of the pancreatic duct is reported. Cytological evidence acinar cell damage is evident from the beginning and loss of zymogen granules occurs early. The acini diminish in size rapidly from the 36th hour to the 3rd day. The cell deletion appears to occur in 2 phases with apparently different characteristics. The first phase appears to be related to the initial cell damage. The letter phase is more general but of uncertain nature. Considerable proliferation of cells occurs in the ducts resulting, with the few remaining acinar cells, in duct-like structures which themselves undergo involution. The duct changes therefore are not passive but involve continued cell proliferation and cell death over a long period.