Somatostatin is a tetradecapeptide that is widely distributed in the body. It acts on multiple organs in the body and also functions as a neuropeptide affecting electrical activity of neurons. Somatostatin Receptor 2 (SSR2), along with SSR1, is expressed at the highest levels in the stomach and jejunum, cerebrum and kidney, respectively. Somatostatin acts to regulate numerous physiological processes by binding to and activating specific receptors in target tissues. Activation of these receptors by somatostatin, which is secreted by nerve and endocrine cells, regulates the secretion of insulin, glucagon and growth hormone, neuronal excitability in both the brain and the peripheral nervous system, and cell growth. Somatostatin receptors have been implicated in numerous diseases ranging from Alzheimer's to cancers of the gastrointestinal tract, breast, prostate, and pituitary. Somatostatin was originally isolated from the hypothalamus and characterized by its ability to inhibit release of growth hormone from the pituitary gland. It exists in two forms, somatostatin-14, composed of 14 amino acids and somatostatin-28, a prohormone composed of 28 residues.