Figure 4.

Thin-layer chromatography analysis of ³H crossing the tissue from selected ³H-bradykinin and ³H-oxytocin flux experiments. The radiochromatograms shown are representative of the total radioactivity present in the serosal fluid compartment at the end of a 180 min flux period from the DMSO (A, D) and omeprazole (B, E) conditions. There are no obvious differences in the proportion of ³H-peptide and ³H-metabolites in either condition. The chromatographic profiles of pure ³H-bradykinin (C) and pure ³H-oxytocin (F) are also shown. 1 cm strips of the chromatogram were cut from the origin to the solvent front. Each strip was counted in a scintillation counter to determine the cpm. The location of ³H-bradykinin or ³H-oxytocin on the chromatogram was detected by its blocking of fluorescence at the origin under a short-wave UV lamp. All radiochromatograms were run in an isopropanol/water/NH₄OH (120:30:1) solvent system on silica gel 60 plates with a 254 fluorescent indicator.