CU ZN-SOD IN HUMAN PANCREATIC TISSUE AND PANCREATIC-JUICE/

Conclusion, Cu/Zn-SOD is present in pancreatic juice and tissue, Immun ohistochemical studies reveal a localization of this enzyme in islet, duct, and centroacinar cells, but to a much lower extent in pancreatic acinar cells, Background, It is generally accepted that oxygen radica ls are involved in the pathogenesis of acute and chronic pancreatitis. An imbalance of radical-generating and radical-scavenging processes i s thought to lead to the damage of pancreatic acinar cells that initia te the autodigestion of the whole organ. Methods, We investigated the distribution pattern of the cytosolic radical-scavenging enzyme, coppe r/zinc-superoxide dismutase (Cu/Zn-SOD), in pancreatic juice and tissu e. In patients with chronic pancreatitis or pancreatic malignancies, C u-Zn-SOD was quantitated in different fractions of pancreatic juice by means of an enzyme immunoassay using two Cu/Zn-SOD-specific monoclona l antibodies. Cryostat or paraffin sections of pancreatic tissue were analyzed by immunohistochemical techniques. Results, We found this enz yme to be present in the first secretin-triggered fraction of endoscop ically obtained pancreatic juice in concentrations similar to serum. I n contrast, after cholecystokinin stimulation, only low levels could b e found in pancreatic juice, indicating that this enzyme is not active ly secreted. Interestingly, pancreatic juice of patients with chronic pancreatitis or pancreas tumor contained higher levels (25-29 ng/mL) o f Cu/Zn-SOD than juice of controls without pancreatic diseases (15 ng/ mL). Immunohistochemical studies of Cu/Zn-SOD in pancreatic tissue rev ealed a more intense staining of duct cells, islet cells, and centroac inar cells, whereas acinar cells showed almost no staining for Cu/Zn-S OD.