[Biochemical and functional changes in experimental acute pancreatitis in the rat].

To discover the biochemical alterations occurring in the first 24 hours of acute pancreatitis (PA), we made an experimental study using rats. We used 90 animals in which necrosis and hemorrhage were induced by closing the choledochus. Animals underwent evolutive periods of 1, 2, 3, 4, 5, 6, 12, 18 and 24 hours. They were sacrificed and plasma (to determine amylase, lipase, creatinine and calcium), urine (amylase and creatinine), ascitic and pleural liquid (amylase and lipase) were obtained from 6 animals of each evolutive period. We made a post-mortem study of the pancreas of three animals of each subgroup. There was a significant increase in the amylasemia from the third hour (p less than 0.005) and of plasmatic lipase from the first hour (p less than 0.0001). Creatinine values remained in normal range and calcemia fell after the sixth hour (p less than 0.001). There was an increase in amylase concentration in urine and in ascitic and pleural liquids, and of the lipase in the last two. These changes correlated with the duration of the disease and with the histologic changes of the gland, which consist in edema, acinar necrosis, vasculitis and hemorrhage, which are present from the first hour and increase as time passes.