Distribution of pepstatin and statine following oral and intravenous administration in rats. Tissue localisation by whole body autoradiography.

The distribution in rats of two radiolabelled derivatives of the potent pepsin inhibitor, pepstatin A, has been monitored by whole-body autoradiography. There was a very poor absorption of pepstatinyl-[14C]glycine and N-[3H]acetylstatine across the gastric and intestinal mucosae after oral administration. Both inhibitors were rapidly cleared from the blood by the liver and kidneys after intravenous administration. Neither inhibitor was localised in the gastric mucosa at a concentration that could be expected to be effective in inhibiting intracellular pepsin activity.