DISTRIBUTION AND CHARACTERIZATION OF IMMUNOREACTIVE ADRENOMEDULLIN IN PORCINE TISSUE, AND ISOLATION OF ADRENOMEDULLIN[26-52] AND ADRENOMEDULLIN[34-52] FROM PORCINE DUODENUM

Using a sensitive radioimmunoassay which recognizes the carboxy-terminal region of porcine adrenomedullin, the distribution of immunoreactive adrenomedullin was investigated in the porcine central nervous system and in peripheral tissue. Adrenomedullin was widely distributed in porcine tissue, and its concentration was highest in adrenal medulla (126+/-32 fmol/mg wet tissue, mean+/-SD). Relatively high concentrations of immunoreactive adrenomedullin were found in the right atrium, lung, duodenum, and pituitary gland, The molecular form of immunoreactive adrenomedullin in all porcine tissues was found to be almost wholly porcine adrenomedullin itself by analysis with reverse-phase high-performance liquid chromatography coupled with radioimmunoassay. Minor molecular forms of immunoreactive adrenomedullin were found in the porcine duodenum. These were isolated and identified as adrenomedullin [26-52] and adrenomedullin [34-52].