| Abstract: | Morphometry was used to study the action of an enkephalin analog and beta-endorphine on the duodenal mucosa in rats with an experimental ulcer induced by cysteamine. Enkephalin produced a more powerful protective action than endorphine. The antiulcerous action was manifested in the diminution of dystrophic changes, redistribution of inflamed cells with an increase in the lymphocyte and monocyte counts, and in the reduction of the number of tissue macrophages and histocytes. Administration of opioids provoked a particularly marked increase in the eosinophil count in the duodenal mucosa. All these effects were abolished by naloxone. It is concluded that the tissue effects of opioids are mediated by specific opiate receptors. |
