Somatostatin inhibits the release of somatotropin. Pancreas. O-linked glycan consists of Gal-GalNAc disaccharide which is modified with sialic acid residues (microheterogeneity). Biological activity of somatostatin-22 on rat pituitary cells was found to be only 0.01-0.1% of somatostatin-14 activity. Belongs to the somatostatin family.