[Acute pancreatitis induced by bile trypsin: structural and ultrastructural study].
The early lesions induced in the pancreas of dogs by the intraductal injection of bile-trypsin were studied. Histological, histochemical and electron microscopic techniques were used. The primary lesions analyzed thirty three minutes after the induction of pancreatitis consisted in cell alterations, blood stasis and oedema. At first, the affected acinar cells showed enlargement of the rough endoplasmic reticulum cisternae, later they were disrupted and then appeared vesicles with ribosomes adhering to the external surface. Mitochondria were swelled and showed cristae disrupted which finally appeared destroyed. The zymogen granules lost density, decreased in size and number and later disappeared, Ducts maintained the normal structure and their cells were still observed in areas where the tissue was greatly destroyed. the results obtained suggest that: 1) The experimental acute pancreatitis induced by bile-trypsin is characterized by primary and severe damage in the acinar cells, with secondary ischemia due to stasis and intravascular coagulation. 2) Cellular rests and probably endogenous enzymes invade the periacinar spaces, then would penetrate into the vascular system producing the generalization of lesions.