Amino Acid Sequence

Ser-Ala-Asn-Ser-Asn-Pro-Ala-Met-Ala-Pro-Arg-Glu-Arg-Lys-Ala-Gly-Cys-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys [Disulfide Bridge: 17-28]

Application

Somatostatin 28 has been used to assess the effects of somatostatinon GH (growth hormone)-stimulated IGF-I (insulin-like growth factor-I) expression.

Somatostatin 28 has been used to study the effects of somatostatin in regulating hepatic growth hormone sensitivity. It has also been used to study its effects on insulin-like growth factor-I receptor expression in the gills of Oncorhynchus mykiss (a teleost fish).

Biochem/physiol Actions

Somatostatin action is delivered with help of five different receptor subtypes (sst1 to sst5).

Somatostatin plays an important role in regulating the metabolism of other hormones such as growth hormone, insulin, IGF-1 (insulin-like growth factor 1), glucagon, glucagon-like peptide and gastrin. Somatostatin has both regulatory and inhibitory functions. It retards gastrointestinal motility and gallbladder contraction, suppresses gut exocrine secretion and reduces epithelial proliferation. Somatostatin is associated with intestinal nutrient absorption and blood flow regulation. This peptide hormone is believed to inhibit cell proliferation and promote apoptosis. Somatostatin acts as a neurotransmitter and neuromodulator, and is also associated in maintaining water balance.

General description

The somatostatin gene codes for a peptide hormone containing 14 and 28 amino acid moieties. SST-14 is highly expressed in the central nervous system and peripheral organs. SST-28 is mainly expressed in enteroendocrine cells of the intestine.

The SST gene is mapped to human chromosome 3q27.3. Both SST-14 and SST-28 are cyclic peptide.