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.