Abstract
Prostaglandins are 20-carbon cyclic fatty acids synthesized from dietary fatty acids by virtually all mammalian cells. These naturally occurring compounds are biologically active, affect most cellular functions, and have both physiologic and pharmacologic effects in animals and in humans. Prostaglandins (PG) represent one of two known groups of arachidonic acid metabolites, collectively known as eicosanoids (Fig. 1). Because of their gastric acid antisecretory effects, as well as their ability to enhance gastroduodenal mucosal integrity, PG have undergone extensive evaluation in animals and in human subjects as potential antiulcer drugs. Naturally occurring PG are rapidly metabolized by enzyme systems present in most tissues, particularly in the lungs, liver, and gastrointestinal (GI) tract, so that their actions are short-lived, unless they are administered by constant infusion in relatively high concentrations. A number of metabolically stable PG analogues have been synthesized that are not only more potent than their natural counterparts but are also active by the oral route. This chapter reviews some of the data supporting a physiologic and therapeutic role for PG in maintaining mucosal integrity.
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Annotated Bibliography
Agrawal NM, Godiwala T, Arimura A, et al: Comparative cytoprotective effects against alcohol: Misoprostol versus cimetidine. Dig Dis Sci 31(suppl): 142S, 1986 (abst). The importance of this contribution is that it provides evidence for the superior effect of a prostaglandin in preventing mucosal damage when a non-acid-dependent experimental model is used.
Agrawal NM, Roth S, Mahowald M, et al: Misoprostol coadministration heals aspirin-induced gastric lesions in rheumatoid arthritis patients. Gastroenterology 92:1290, 1987 (abst). This abstract provides important data on the healing effect of a prostaglandin on gastric lesions, during continued chronic administration of aspirin. Not included in this abstract, but presented at a symposium held during Digestive Disease Week in 1987, are data showing similar (but less effective) efficacy in duodenal ulcers in this group of patients.
Ahlquist DA, Dozois RR, Zinmeister, AR, et al: Duodenal prostaglandin synthesis and acid load in health and in duodenal ulcer disease. Gastroenterology 85:522–528, 1983. In this study, the investigators did not find a significant difference between PG in the ulcer and nonulcer groups with respect to total measurements. However, they did find that ulcer patients synthesized less PG relative to the amount of acid perfusing the duodenum, thereby confirming the original work of Wilson’s group.
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© 1989 Plenum Publishing Corporation
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Wilson, D.E. (1989). Cytoprotective Therapy Prostaglandins. In: Hollander, D., Tarnawski, A.S. (eds) Gastric Cytoprotection. Springer, Boston, MA. https://doi.org/10.1007/978-1-4684-5697-4_9
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DOI: https://doi.org/10.1007/978-1-4684-5697-4_9
Publisher Name: Springer, Boston, MA
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