Calcium Concentration and Artificial Precipitates in Human Pancreatic Juice

Abstract

We studied the role of the increase in the calcium concentration in pure pancreatic juice of alcoholic noncalcified chronic pancreatitis. Pure pancreatic juice was obtained endoscopically. The pancreatic juice from patients with chronic pancreatitis was adjusted to pH 7.5; then the calcium concentration was adjusted to 0.4, 2.9, 5.4, or 10.4 mmol/L. Artificial precipitates were produced by incubation of the samples at 37 degrees C for 6 hours. Proteins in the artificial precipitates were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and the protein patterns were compared with the patterns of natural protein plugs from patients with chronic pancreatitis. The amount of the precipitate increased as the added calcium increased. The protein patterns of SDS-PAGE of the artificial precipitates were similar to those of protein plugs. Albumin, a-amylase, lipase, trypsinogen, and chymotrypsinogen were identified by immunoblotting both in the precipitate and in the protein plug. The increased calcium concentrations in pancreatic juice induced the formation of precipitates whose protein composition was similar to that of protein plugs. An increased calcium concentration in human pancreatic juice may play an important role in the pathogenesis of protein plugs.

Increased Activation of Hereditary Pancreatitis-associated Human Cationic Trypsinogen Mutants in Presence of Chymotrypsin C

“…The autoactivation experiments presented here were performed in the presence of 1 mM CaCl 2 . In human pancreatic juice, total calcium concentrations between 0.2 and 0.9 mM were reported, with higher values found in patients with chronic pancreatitis (31)(32)(33). One study reported ionized calcium concentrations at 0.3 mM, with 0.6 mM total calcium (32).…”

Pancreatitis complicated with dilated choledochal remnant after congenital choledochal cyst excision

“…The etiology of pancreatic protein plug formation remains uncertain. Some investigators have suggested an increased viscosity of pancreatic juice due to elevated protein concentrations, leading to protein plug formation and a temporary blockage of the pancreatic duct by a protein plug, a pancreatic calculus, or a dysfunction of the sphincter of Oddi [1,14,15]. The obstruction of the pancreatic output may cause dilatation of the choledochal remnant.…”

Pancreatitis After a Primary and Secondary Excision of Congenital Choledochal Cysts

“…Some studies have indicated that the increased viscosity of the pancreatic juice is the result of elevated protein concentrations, thus leading to protein plug formation and a temporary blockage of the pancreatic duct by a protein plug, pancreatic calculi, or dysfunction of the sphincter of Oddi. 1,7,8 The blockage of the pancreatic output may cause dilatation of the pancreatic duct and lead to abdominal pain; 9 however, the symptoms were of a transient nature because of the small size of the plug in this patient. Endoscopic irrigation is thus the preferred treatment to remove the plug.…”