Background:
Acute pancreatitis (AP) is a poly-etiological disease with complex pathogenesis.Mortality rate in AP ranges from 26% to 85%.Clinical manifestations of AP is associated with impaired function of the exocrine function of the pancreas and it develops either due to insufficient production of digestive enzymes or their premature activation Objective : The purpose of the investigation is to study the morphological changes of the pancreas in rats with acute pancreatitis in the dynamics,taking into account the phases of development of the pathological process.

Material and Methods:
The model of experimental AP was created by chloroethyl cryodestruction of the splenic segment of pancreas of 40outbred white rats weighing180-220g.The pancreatic tissue specimen were taken after at 1,3,7,14 days after surgery.Key parameters selected to evaluate the morphological condition of the exocrine parenchyma includes: nuclear area, cytoplasmic area and nuclear-cytoplasmic ratio of acinarcells

Result:
On the 1st day there was a sharp decrease in the nuclear area and acinar cell, On the 3rd day there was an increase in the average nuclear area,by the 7th day of pancreatitis there was a slight increase in the cytoplasmic area, at the 14th day of AP nuclear –cytoplasmic ratio was high ,indicating the recovery process in the survived parts of the exocrine parenchyma.

Conclusion:
complex morphometric study of cells of the exocrine parenchyma of pancreas in experimental AP in rats contributes to the definition of the morphological criteria of metabolic disorders in the affected organ at various stages of the pathological process