Effect of cholecystokinin blockade on the recovery of alterations induced by acute pancreatitis in glycoconjugates of rat zymogen granules

Lectin-binding studies have been performed on rat zymogen granules to inves tigate alterations in the carbohydrate membrane composition that occur in a cute pancreatitis induced by caerulein. The influence of treatment with hyd rocortisone for seven days before inducing pancreatitis was also studied. L ectin labeling on zymogen granules was also analyzed seven days after induc ing pancreatitis in rats that had previously received a hydrocortisone trea tment. During this period L 364,718 (0.1 mg/kg)-specific cholecystokinin (C CK) receptor antagonist-was administered daily to some of the rats, and no treatment was applied to others. Using fluorescein-labelled T. purpureus (T P) lectin, a significant decrease in the amount of L-fucose in the granule membrane was observed in rats with caerulein-induced pancreatitis. This eff ect was directly caused by the pancreatitis and was not influenced by previ ous hydrocortisone treatment. Seven days later, the density of TP receptors in the granule membrane was similar to the controls both in L-364,718-trea ted and untreated rats. Therefore, we suggest that endogenous CCK is not an essential factor in the recovery of L-fucose containing glycoconjugates th e granule membrane after pancreatitis. Acute pancreatitis did not alter the expression of wheat germ agglutinin (WGA) receptors in the zymogen granule membrane. WGA specifically binds N-acetyl glucosamine and sialic acids, L 364,718 administered for seven days after inducing pancreatitis significant ly reduced WGA binding, untreated rats showed a normal zymogen granule memb rane. Therefore, the blockade of CCK-induced alterations in membrane glycoc onjugates enriched in N-acetyl glucosamine and sialic acid of newly formed granules after pancreatitis, a finding that could explain the delay in the regression of the disease.