inhibition of the release of numerous secondary hormones. Somatostatin inhibits insulin and glucagon secretion.

Somatostatin has two active forms produced by the alternative cleavage of a single preproprotein: one consisting of 14 amino acids (shown in infobox to right), the other consisting of 28 amino acids. Alternate cleavage sites of the SST preproprotein results in the production of the hormone Neuronostatin, which has two active forms as Neuronostatin-13 and Neuronostatin-19. Neuronostatin is