Diverse effects of phytohaemagglutinin on gastrointestinal secretions in rats

Citation
K. Kordas et al., Diverse effects of phytohaemagglutinin on gastrointestinal secretions in rats, J PHYSL-PAR, 94(1), 2000, pp. 31-36
Citations number
31
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences & Behavoir
Journal title
JOURNAL OF PHYSIOLOGY-PARIS
ISSN journal
0928-4257 → ACNP
Volume
94
Issue
1
Year of publication
2000
Pages
31 - 36
Database
ISI
SICI code
0928-4257(200001/02)94:1<31:DEOPOG>2.0.ZU;2-4
Abstract
Kidney bean lectin phytohaemagglutinin (PHA) is known for its binding capac ity to the small intestinal surface inducing marked hyperplasia and hypertr ophy and an increased pancreatic function. Recent observations indicate tha t PHA is able to attach to gastric mucosal and parietal cells. Therefore, w e compared the effects of PHA on gastric acid secretion, and pancreatic amy lase secretion in rats. To study gastric secretion in conscious animals, ra ts were surgically prepared with chronic stainless steel gastric cannula an d with indwelling polyethylene jugular vein catheter. Acid secretion was de termined by titration of the collected gastric juice to pH 7.0. Similar stu dies were performed to investigate the effect of PHA on pancreatic enzyme s ecretion in conscious rats supplied with pancreatic cannula. Pancreatic enz yme secretion was also studied in rats anesthetized with either halothane o r urethane. In conscious rats PHA significantly inhibited basal acid secret ion when compared to vehicle-treated controls. The effect was dose-dependen t and reversible. On the other hand, given in the same doses as in the acid -secretory studies, PHA stimulated pancreatic amylase secretion in rats pre pared with chronic pancreatic cannula. This effect was blocked by devazepid e, a CCK-A receptor antagonist. In halothane-anesthetized rats PHA administ ration increased pancreatic amylase secretion, too. During urethane anesthe sia, however, the stimulatory effect of PHA was not observed. These results provide evidence that intragastric PHA treatment induces opposite effects on gastric acid secretion and pancreatic enzyme secretion: it is a potent i nhibitor of acid output, and a stimulator of pancreatic enzyme discharge. O ur data also show that the stimulatory effect of PHA on pancreatic enzyme s ecretion can be blocked by urethane, an anaesthetic that is known to turn o ff the negative pancreatic feedback control of pancreatic function in rats. (C) 2000 Elsevier Science Ltd. Published by Editions scientifiques et medi cales Elsevier SAS.