A preprohormone is the precursor protein to one or more prohormones, which are in turn precursors to peptide hormones.[1] In general, the protein consists of the amino acid chain that is created by the hormone-secreting cell, before any changes have been made to it. It contains a signal peptide, the hormone(s) itself (themselves), and intervening amino acids. Before the hormone is released from the cell, the signal peptide and other amino acids are removed.[2] [3]