[Effects of calcium overload in the conversion of acute edematous pancreatitis to necrotizing pancreatitis in rats].
OBJECTIVE
To investigate the potential of pancreatic acinar cell calcium overload in the conversion of acute edematous pancreatitis (AEP) to necrotizing pancreatitis (ANP).


METHODS
Ninety-six Sprague-Dawley rats were randomized in three experimental groups. Sham-operated control (Group I) AEP (Group II) was induced by pancreatic duct ligation and intravenous injection of bombesin (100 micrograms/kg) and secretin (10 micrograms/kg). ANP (Group III) was induced same as group II but with a large dose of dextran 110,000(500 mg/kg) intravenously. Pancreatic acinar cell Ca2+ overload was studied using fluorescent probe Fura2. Cytosolic free Ca2+ concentration ([Ca2+]i) in isolated pancreatic acinar cells and Ca(2+)-ATPase activity in pancreatic cell plasma membranes were determined 1, 3, 6, 9 h respectively after treatment.


RESULTS
The results showed that pancreatic acinar cell [Ca2+]i was elevated at 1 h[(213 +/- 19) nmol/L, P < 0.05] and increased to (464 +/- 29) nmol/L at 6 h(P < 0.05) in rats with ANP, pancreatic cell plasma membrane Ca(2+)-ATPase activity decreased significantly from (29.8 +/- 0.4) nmol.min-1.mgp-1 at 1 h to (18.6 +/- 0.5) nmol.min-1.mgp-1 at 9 h in rats with ANP (P < 0.05).


CONCLUSIONS
In ischemia-induced conversion of AEP to ANP, there exists Ca2+ overload in the pancreatic acinar cells. The decreased pancreatic cell plasma membrane Ca(2+)-ATPase activity may be an important reason for acinar cell Ca2+ overload in the development of acute pancreatitis.
Pu
Q
Q
Department of General Surgery, First University Hospital, West China University of Medical Sciences, Chengdu 610041.
Yan
L
L
Shen
J
J
D000818:Animals; D001693:Biological Transport, Active; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism; D005260:Female; D008297:Male; D010179:Pancreas / Q000378:metabolism*; D010195:Pancreatitis / Q000378:metabolism*; D019283:Pancreatitis, Acute Necrotizing / Q000209:etiology / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
D000252:Calcium-Transporting ATPases; D002118:Calcium