Influence of pancreatic surgery on gastric ulcers and somatostatin-like immunoreactivity in portal and aortic blood, and in the gastrointestinal tissues of the rat.

Two weeks after pancreatic duct occlusion (OCC) or pancreatic half-resection (RES) in rats, the development of gastric ulcers was assessed. Somatostatin-like immunoreactivity (SLI) was measured simultaneously in portal and aortic blood as well as in fundic, antral, duodenal and pancreatic tissue specimens. Extracts of antral, duodenal and pancreatic tissue were chromatographed on a Sephadex G25 superfine column (1.6 +/- 90 cm) under strongly dissociating conditions. As compared to sham-operated controls (SHAM) ulcer index in arbitrary units (AU) and ulcer severity were significantly increased in duct-occluded rats (ulcer index: 5.6 +/- 1.9 AU in SHAM, 42.6 +/- 7.9 AU in OCC; severity: 0.47 +/- 0.37 mm in SHAM, 9.76 +/- 2.37 mm in OCC; p less than 0.001 respectively). Aortic SLI was increased in both experimental groups (SHAM: 53.2 +/- 7.4 pg/ml; RES: 110.9 +/- 16.6 pg/ml, p less than 0.01 vs SHAM; OCC: 96.0 +/- 9.0 pg/ml, p less than 0.001 vs SHAM); portal SLI was decreased in duct-occluded rats (SHAM: 88.9 +/- 7.1 pg/ml; OCC: 65.7 +/- 9.9 pg/ml; p less than 0.05). Tissue SLI was raised in the gastric fundus of duct-occluded rats (SHAM: 6.4/1.3-36.1 micrograms/g; OCC: 8.2/5.1-14.9 micrograms/g; p less than 0.05) and in the duodenum of resected animals (SHAM: 0.7/0.2-1.6 micrograms/g; RES: 1.4/0.4-2.3 micrograms/g; p less than 0.05), but decreased in the duct-occluded pancreas (SHAM: 3.7/1.0-8.2 micrograms/g; OCC: 2.1/0.5-5.6 micrograms/g; p less than 0.05). In all three groups, the major part of total SLI in antrum, duodenum and pancreas was identical with somatostatin-14 at gel chromatography.(ABSTRACT TRUNCATED AT 250 WORDS)