Peritoneal fluid in human acute pancreatitis blocks hepatic mitochondrial respiration.

Peritoneal fluid may be the source of multi-system failure during the initial stages of acute pancreatitis. The toxicity of human pancreatic ascitic fluid (HPAF) collected under sterile conditions from 12 patients with acute pancreatitis was investigated with the use of an in vitro preparation of mitochondria. Hepatocyte mitochondria from Sprague-Dawley rats were prepared by standard techniques. Mitochondrial oxidative activity was determined in glutamate-malate medium, with micromodification of the YSI Model 53 (Yellow Springs, Ohio) oxygen electrode system. The oxygen uptake of 150 to 200 microliter samples of mitochondria suspension (20 to 25 mg/ml) was monitored for 3 minutes, after which 3 microliter of 0.1 M adenosine diphosphate (ADP) was added to the chamber to induce state 3 respiration. Two minutes after the oxygen trace returned to state 4 respirations, 20, 40, or 80 microliter of the HPAF sample was introduced into the reaction vessel and the oxygen measurement continued for an additional 3 minutes. After this, 3 microliter of 0.1 M ADP again was added to the reaction chamber and the oxygen measurement continued. Control runs were made with reconstituted pooled human serum used in place of the HPAF samples. A significant (p less than 0.05) increase in state 4 respiration occurred in all 12 samples of HPAF. Addition of ADP showed a significant decline (p less than 0.05) in respiratory control ratio in all specimens. A dose-response curve was observed in 8 of 12 HPAF samples tested.(ABSTRACT TRUNCATED AT 250 WORDS)