Tests whether salivary glands are required for the anti-ulcer activity of BPC 157 and standard agents against cysteamine-induced duodenal ulcers. In intact and gastrectomized rats, all agents (BPC 157, ranitidine, atropine, omeprazole) protected against cysteamine duodenal lesions via acid-independent mechanisms. After acute or chronic sialoadenectomy (salivary gland removal), ranitidine, omeprazole, and atropine became completely ineffective, while BPC 157 retained its protective effect. Demonstrates that standard anti-ulcer agents require intact salivary glands while BPC 157 can replace salivary gland-dependent factors—a distinct and potentially superior cytoprotective mechanism.
Abstract
The focus was on salivary glands in cysteamine-induced duodenal ulcer and the different effects of antiulcer agents on cysteamine-induced duodenal ulcer in sialoadenectomized but not gastrectomized rats. We tested antiulcer agents on cysteamine-induced duodenal ulcer in rats (agents/kg i.p.) simultaneously with cysteamine 400 mg/kg s.c., rat killed 24 h thereafter subjected to no surgery (normal), to gastrectomy (24 h before) or sialoadenectomy, acute (24 h before) or chronic (21 days before). (i) Ulcerogenesis: cysteamine-induced duodenal ulcer had the same severity and incidence in normal, gastrectomized or acutely or chronically sialoadenectomized rats. (ii) Antiulcer effect under normal conditions or following gastrectomy: in normal or gastrectomized rats all agents tested, gastric pentadecapeptide BPC 157 [currently in clinical trials for inflammatory bowel disease (PL-10, PLD-116, PL-14736, Pliva) (10.0 microg or 10.0 ng), ranitidine (10 mg), atropine (10 mg), omeprazole (10 mg)] inhibited cysteamine-induced duodenal ulcers, acting through gastric acid-independent mechanisms. Following sialoadenectomy, acute or chronic: ranitidine, omeprazole and atropine were completely ineffective, while pentadecapeptide BPC 157 could protect. Thus, we found that contrary to stomach, salivary glands are implicated in cytoprotective agent activity (standard agents were ineffective after sialoadenectomy). Also, gastric pentadecapeptide BPC 157 was consistently associated with a cytoprotective effect, suggesting a beneficial activity distinctive from that of H2-receptor blockers, proton-pump inhibitors and anticholinergics; but probably replacing missing salivary glands factors.