Pro-Adrenomedullin(153-185),human, (C143H224N42O43), a peptide with the sequence H2N-SLPEAGPGRTLVSSKPQAHGAPAPPSGSAPHFL-OH, MW= 3219.6. Adrenomedullin (AM) is a ubiquitously expressed peptide initially isolated from phaechromyctoma in 19931. AM was initially identified as a vasodilator, some have cited this as the most potent endogenous vasodilatory peptide found in the body2. Differences in opinion regarding the ability of AM to relax vascular tone arises from the differences in the model system used3. Other effects of AM include increasing the tolerance of cells to oxidative stress and hypoxic injury and angiogenesis. AM is seen as a positive influence in diseases such as hypertension, myocardial infarction, chronic obstructive pulmonary disease and other cardiovascular diseases, whereas it can be seen as a negative factor in potentiating the potential of cancerous cells to extend their blood supply and cause cell proliferation.