Effect of 16,16-dimethyl prostaglandin E2 on gastric mucus gel thickness.

Direct measurements of the thickness of the layer of insoluble mucus gel lying on the gastric mucosa were made by using a slit lamp and an image-splitting system. Under resting conditions, the thickness (mean +/- SE) of the mucus gel on the gastric mucosa was 166 +/- 10 micrometers in the rat, 234 +/- 9 micrometers in the guinea pig, 429 +/- 17 micrometers in the dog and 576 +/- 81 micrometers in the human. Using a pylorus ligated rat model, topical application of 16,16-dimethyl prostaglandin E2 to the mucosa in concentrations of 1 microgram/ml and 10 micrograms/ml caused a dose dependent increase of the thickness of the mucus gel layer of 81% and 140% respectively. This drug-induced increase in mucus gel thickness may contribute to the cytoprotective effects of this prostaglandin analog.