On the biochemical background of cysteamine-induced duodenal ulceration in the rat.
In cysteamine-induced duodenal ulceration the endogenous prostacyclin level initially showed an elevation. This elevation later disappeared, and the endogenous prostacyclin level dropped to zero--that is, below the detection limit. During ulceration the mucosal DNA level decreased, a phenomenon that was directly proportional to ulceration. In the course of the ulcerative process in the duodenal mucosa a de novo protein synthesis took place. This process was most probably a mucus secretion and served as a protective reaction against damaging noxae. The mucosal cyclic adenosine 5'-monophosphate (cAMP) content increased in the so-called pre-ulcerative phase but later returned to the normal (physiologic) level. The changes in the cyclic guanosine 5'-monophosphate (cGMP) level were more pronounced than those of cAMP, and the final result was a decrease in the mucosal cAMP/cGMP ratio. In accordance with our previous results we conclude that a positive cAMP/cGMP 'shift' indicates antiulcerogenic, cytoprotective, reparative processes in the mucosa, whereas its decrease is connected to damaging noxae.
Balint
G A
GA
Dept. of Neurology and Psychiatry, Albert Szent-Györgyi Medical University, Szeged, Hungary.
D015121:6-Ketoprostaglandin F1 alpha / Q000378:metabolism; D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D003543:Cysteamine; D004247:DNA / Q000378:metabolism; D004381:Duodenal Ulcer / Q000139:chemically induced* / Q000378:metabolism; D005260:Female; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism; D009093:Mucus / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D015121:6-Ketoprostaglandin F1 alpha; D003543:Cysteamine; D012313:RNA; D004247:DNA; D000242:Cyclic AMP; D006152:Cyclic GMP