Peptide, Protein, and Glycoprotein Hormones

Cells that produce peptide, protein, or glycoprotein hormones are derived embryologically from the entoderm or ectoblast (progenitor of ectoderm and neuroectoderm). More than 40 hormones have been identified, containing from three to over 200 amino acid residues. Table 30-2 lists the important hormones and hormonal candidates, number of amino acid residues, and sites of synthesis. 

Insulin-like Growth Factor I (IGF-I) 70 Y Cartilage, liver, et al. 

Restricted to those sites that are physiologically important P = paracrine function S = released into blood. 

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